Pros:

* Incredible attention to detail.
* Good lighting and atmosphere.
* No distance fog at all, increased realism.
* Almost everything is interactive.
* Several fully functional rides.
* Great overall gameplay.
* Super innovative finale.
* Flawless survivor dialogue and monologue.

Cons:

/ Not very challenging.
/ Poor optimization in most maps (check conclusion).

Conclusion:

This is hands down one of the most completely and absolutely greatest L4D2 custom campaigns I've ever played - and somehow, I managed ignore it for so long before trying it out. I played it from start to end on Advanced with a friend, and we had a blast.

The only real problem with it was that the optimization seemed somewhat sluggish; I was getting 80 - 110 FPS on average out of my usual 140 - 300, at one point even dropping to 45. It was even worse for my friend who reached as low as to 5 FPS, out of his usual 20 - 40.But besides that, I have absolutely nothing to really complain about. This is definitely a must-try for anyone who hasn't played it yet. 

10/10.

Pros:

* Scripted events (towers falling, floor breaking etc.)
* Unique in its own way.
* Fairly entertaining.

Cons:

/ Ugly visuals - gray fog, bad lighting etc.
/ Crowded supply spots. Loot should have been scattered around instead.
/ Map 2 was way too easy - managed to complete it with no damage taken on advanced with one other player.
/ Pointless cutscenes.
/ Endless horde in the finale.
/ Short maps.
/ Ugly, texture-less water.
/ Very linear, hardly any alternative paths.

Conclusion:

It clearly needs work but it still feels like *some* effort was put into it. Bad visuals, way too much loot and lack of overall variety. With some work it could probably be made better.

Pros:

* New paths.
* New props, obstacles, etc.
* Somewhat entertaining.
* You tried, I guess.

Cons:

/ Loot and weapons everywhere...
/ Way too many arrows telling you where to go.
/ Huge, pointless load of bodies in the saferoom.
/ Massive, pointless ladder overlapping a window in the beginning.
/ No actual obstacles, just walking and climbing ladders.
/ Three tanks in the train that can barely get past each other.
/ Shorter than the original.
/ Way too easy to escape tanks.
/ Stop removing people's comments, seriously.

Conclusion:

I decided to try this when my friend told me to find the worst campaign of all time. Honestly, I've seen worse - but yes, it's still quite horrible.

Pros:

* Almost flawlessly ported, everything is as it was.
* Everything works - elevators, ladders doors etc.
* Good item placement.
* Great and challenging finale.

Cons:

/ Lacks the lift that brings you over the wall to the church.
/ World collisions in the graveyard and cave seem buggy.
/ No dialogue, but barely any campaigns have that anymore anyway.

Conclusion:

A great port of HL2's creepy village, Ravenholm. Everything seemed to be there, except the city lift, but that doesn't matter too much. The train tracks and finale were probably what we enjoyed the most when playing it. There's no cons that affect the entertainment level too heavily, and the final rating ends up on a 9.9.

Pros:

* Flawless, and very detailed model.
* Uses flashlight-friendly animations.
* High-poly flashlight model.
* Great new sounds.
* Great VMT mixing.

Cons:

/ Somewhat ugly, oversaturated textures.
/ Flashlight color doesn't fit the base textures at all.
/ Barrel looks like white concrete rather than shiny metal.
/ Would prefer it without the shell carrier. No points deducted.

Conclusion:

After avery long break with no new models for the M1014, there's finally a great new mod for it. Kruku's M1014 has always been one of my favourite models in Source games, and I've always been hoping to see it ported to L4D2 one day. I've never been a fan of the bland and stone-like textures, but the great VMT scripting puts up with that.

9.6/10.

Pros:

* Great atmosphere.
* High level of overall detail.
* Survivor dialogue.
* Smooth cutscenes (especially intro).
* Wide, non-linear environments.
* Custom SI models, textures & sounds.
* Custom ambient soundtracks.
* Puzzles.
* Huge maps.
* Fun and challenging gameplay.
* Very few survivor closets. Instead, more defib units.
* Weapons and items only spawn singly, not in stacks.
* Good performance, no unexplainable slowdowns.
* The Sewers map deserves a mention. It's glorious.

Cons:

/ The Otherworld seems too confusing for its length.
/ Can't think of anything else.

Conclusion:

Probably the best L4D2 campaign I've played the last 6 months. It has everything you could ask for - Large and long maps, no overused respawn closets, beautiful visuals, puzzles, custom audio, survivor dialogue, and ofcourse, the perfectly creepy atmosphere.

Only con I can possibly think of is the Otherworld part. The length combined with the confusing bridges and pathways makes it a bit of a pain to get through. But since it's only one map, it doesn't really change the overall entertainment this campaign brings.

(review may be changed when final update is released)

Pros:

* Solid length.
* Entertaining.
* Interesting environments.
* Map 4 is incredibly fun and creative.
* Great and challenging finale. (With low gravity!)

Cons:

/ No dialogue at all.
/ Awful visuals and lighting. Read conclusion for details.
/ ''OMG RUN!'' seemed really cheesey.
/ Force-spawned chargers in the end of map 3.
/ Poor performance in certain areas.
/ Repetitive use of houses in map 2.

Conclusion:

Fun and above average gameplay, a great finale and original environments - No doubt that this campaign is worth playing. Anyhow, calling it flawless would be a lie, and a total lack of loyality. 

[Con #2] - With broken cubemap reflections, bland and unrealistic lighting, awful use of fog and poor performance in a handful of areas, I can't help but decrease the final rating.

[Con #3] - In map 2, a notification will pop up on your screen saying ''OMG RUN!'' - This made my friend and I burst out in laughter, as there was no danger after all and because of the all-caps ''OMG''. NEVER use shortened sentences like OMG, WTF or LOL in your maps/campaigns AT ALL. It's silly and unprofessional, and would never be seen in an official game or campaign.

[Pro #5] - The finale was really awesome and entertaining.Low gravity, an entire circular office to survive in and a long and dark way to the escape pod - I sure as hell would love to see more like that in the future.

In conclusion, a super entertaining campaign with bunch of flaws that shouldn't be too hard to ignore. The final score ends up on a 8.1

Pros:

*Very long - Two intro maps and 7 head maps.
*Almost completely bug-free and well tested.
*Very challenging and fast-paced.
*Non-linear, loads of different paths to go by.
*Based on HL2.
*Nighttime environments.
*Correct use of distance fog.
*Correct lighting.
*Custom explosive barrels from  HL2.
*Destructible props & wood.
*Unique finale.

Cons:

/Force-spawned enemies in certain areas.
/No dialogue at all.

Conclusion:

It's ages since I've played a campaign on this quality. My friend and I finished the campaign in ~2 hours and enjoyed it to the max. The gameplay is smooth, the visuals are just perfect, and nearly everything works flawlessly. Only real con is that there are multiple areas where certain special infected are forced to spawn in, eg. spitters seem to constantly respawn in the storm drain. When looking away from that, this campaign is definitely a clear 10/10.

Pros:

Same good stuff from CS: GO

Visors are actually transparent

First person hands included

Coach has the right skin color

Cons:

FP hands are misplaced when using the auto shotguns

Coach watched too much nope.avi

Shoulders are partially visible in FP with assault rifles

Fingers are pretty buggy in thidperson

Conclusion:

If you look away from all the little problems with the hands, it's a really great and simple pack.

Pros:

High quality textures & bumpmaps
High poly model
First Browning Auto-5 mod on the site
And as always, good animations, but...

Cons:

Honestly, it's starting to get boring how all decent weapon mods on this site uses Arby26's animations. He never updates them, and after downloading 200+ mods using the same animations, it stops being fun.

Conclusion:

A great new mod for the M1014/autoshotgun with high quality textures, model, animations, all that. I don't know why it suddenly starts to bother me that Arby's animations are everywhere, sp dpn't ask - I'm not reducing the final score because of that anyway.

Pros:

Great high quality textures
Good animations
Highly detailed/high poly model
Correctly posed in third person

Cons:

Scope texture is bad - Read conclusion
Chainbelt doesn't move, doesn't really matter though

Conclusion:

In general, it's a great, high-quality mod for the M60 with an all new model, textures, animations and all that. Anyhow, what surprisingly cuts off 0.2 points from the rating is the scope, it really bothers me. It's horribly bright in the edges and literally just looks like a sticker. It has an unnecessary sticker-like lens flare too - If you can't get real transparency and lighting effect, it's better having nothing.

But anyway, before I make it look like I absolutely hate this mod, I'll finish off saying that it's possibly the best mod for the M60 i've seen so far - it ends up on a 9.8

Pros:

High quality model, extremely detailed
High quality textures
Custom body modification, looks great
Held correctly in thirdperson.

Cons:

Uses the default L4D2 animations
Player's left thumb seems to bug out when reloading

Conclusion:

The model is great and is perfectly converted - Anyhow, it doesn't have any custom animations which really ruins a lot.

Pros:

Great, fresh outdoor atmosphere
Large open areas in most maps
Floating 3D text that tells you about your progress
Custom speech - Good job, Edwin
Awesome ascension finale
Traintracks, because I love them

Cons:

Boring indoor textures and atmosphere
Bad water flooding effects
Bots die way too easily in the finale
Hordes sometimes spawn right infront of your eyes
The traintracks tank can be tricked way too easily

Conclusion:

In general, it's a really great new campaign with custom speech and a great 3D information system, but lacks challenge and better indoor atmosphere. Each map is great, and there's even a panic event on a large open airstrip which I really loved.

The indoor texturing seems boring and unrealistic, it's just plain concrete walls with black/yellow warning decals on the edges - not very interesting after all. The outdoor atmosphere, is opposed to the indoor atmosphere, really great. It looks fresh but warm, and fits the mountain/woodland theme very well.

In conclusion, it ends up on a 8.9 and it's definitely a campaign that's worth playing in my opinion.

Pros:

Great animations
High quality textures
High-poly Reflex Sight model

Cons:

Shell ejection mechanism is on both sides of the model (I know there's not much to do about it, though)
Low poly world model, since it's converted from CSS

Conclusion:

A really great shotgun mod, but still pretty far from perfect in my opinion.

Valve did a really bad job with their modeling back when they made Counter Strike: Source, such as placing the shell ejection mechanisms on both sides of the gun, and being lazy with the world models. It seems like there's new high quality textures for this mod's world model, though, which is a huge plus.

Pros:

High audio quality
Gives panic events a more intense stressing feel to it

Cons:

None

Conclusion:

A simple but well-made audio mod that adds a way better atmosphere to the panic events, and additionally it doesn't seem to get out of synchronization like Valve's original drum track.

Pros:

Detailed
Way more realistic and saturated
Modified bumpmaps
High quality - No stretched textures or low resolutions

Cons:

None

Conclusion:

A simple but amazing texture mod for something I doubt I'll ever see another mod for. Valve's original gas items looked way too clean and newly made, having no scratches or rust at all.

Pros:

Much more realistic
High quality
Matches the color of the fog

Cons:

There's a... pretty tall mountain in Dark Carnival's skybox
Kinda ruins the original atmosphere in the maps
The sun is infront of the clouds in most of the skyboxes

Conclusion:

Those are some really great skyboxes that add a whole new atmosphere to the campaigns and look much more realistic.

Personally I can't stand using them though, I miss the original skyboxes and their misty atmosphere - But it's clearly a great mod that's worth downloading.

Pros:

Detailed
Great atmosphere
Fun gameplay
Awesome finale
Creative
Mountains!
Pretty cool ending cutscene

Cons:

Missing textures in some maps
Fairly short
Auto-escape in finale
No dialogue
No opening cutscene
Weird looking fog

It doesn't really make sense at all. You start out in a modern night-time city, then you go into a tunnel and get into a daytime mountain area? Doesn't matter that much though.

Conclusion:

In general, it's a really good campaign - Detailed, good atmosphere, proper lighting and good gameplay. Anyhow, there's no dialogue and no opening cutscene, and you're automatically teleported into the rocket when it's ready.

Other than that, it's a really creative and fun campaign that's definitely worth a download.

Pros:

Fun
Good idea
Good atmosphere

Cons:

Bots fall off easily
Short

Conclusion:

It's really fun and the atmosphere and overall visuals are great, but it's really short and isn't too good for single player due to the bots falling off easily.

Pros:

Attachments!
Custom/modified body
Good model
Really good sight model
High quality textures
Good animations, but... (see con 2)

Cons:

World model is way too small
I still dislike Arby's walk animations
The Mossberg 500 Tac is not automatic in real life

Conclusion:

This model was ported to GTA IV a few weeks ago and I absolutely loved it. The only major con is that the world model is extremely small.

Pros:

Good atmosphere
Detailed
Challenging
Perfect use of panic events
Long
Multiple paths / big open areas

Cons:

Terrible lighting and atmosphere in last map
Third map is pretty confusing
The first saferoom is so unsafe I actually died in it

Conclusion:

Other than the lighting being really bad in the last map and a few other things, the campaign itself is really fun and clearly worth trying.

Pros:

Detailed
Good atmosphere
Good lighting
Challenging finale
Hilarious tank spawn points
Elevator escape! Better than the boring choppers

Cons:

Extremely short
Game freezes sometimes when starting panic events
Didn't see a single witch (-0)

Conclusion:

This campaign has some really fun panic events and lots of tanks, but is also eally short. I really enjoyred running up the stairs and then immediately back down again after looking a tank right in the eyes. With longer, or just more maps, this would be perfect.

Pros:

Good model
Good textures
Better bumbmaps than the old one
Proper texture for his skin near the eyes
v_model hands

Cons:

Helmet doesn't look very good

Conclusion:

Another really good replacement model for Nick with a high quality texture. Personally I prefer the old camo, but the bumpmaps and eye texture on this are way better.

Pros:

Awesome animations
Good texture
Good model

Cons:

Looks too small

Conclusion:

It seems like it's the only replacement model for the Desert Eagle so far, and it has some really good animations. The only thing I don't like is the size.

Pros:

It's soda. Swallowing 100 pills in a second was awkward
New model, not just a boring reskin.

Cons:

Still uses pill sounds, doesn't matter that much though.

Conclusion:

I really like this mod as it replaces the pills with something that's actually drinkable. I've never liked the way you swallowed hundreds of pills in less than a second without water.

Pros:

New model
High quality texture
Bumpmaps
He's a cop... at some point. That, itself, is cool.

Cons:

Francis hates everything, like he always does.

Conclusion:

For some reason, I'm addicted to police/military skins for L4D2, and this is definitely a good one. No cons here.

Pros:

High quality, no jagged edges or unfinished lines.
Cute
Better than the original

Cons:

None

Conclusion:

A really nice and simple mod of the SI icons, no cons as it's simply a HUD update with high quality images.

Pros:

Detailed
Non-linear
Traps
Awesome finale battleground
Custom background music

Cons:

Bad atmosphere, the old nighttime setting was better
Lazy texturing at some places in the finale
Way too many supplies, ammo and medkits everwhere

Conclusion:

The overall gameplay is good, but the new atmosphere and daytime setting is pretty bad and doesn't fit L4D2 at all, it's almost HL2-like. Another thing is that there's supplies everywhere, you never run out of medkits or ammo. Besides from that, one thing that's cool is the custom background soundtracks. 8.4

Pros:

Very detailed and realistic looking
Perfect lighting and atmosphere
Perfect ammount of weapons and supplies
Panic events aren't over-difficult and unfair
Awesome finale
Awesome underground part
Detailed house interior
Funny wall text in safehouses
Lots of conversations between the survivors

Cons:

Sometimes it's too easy to get lost

Conclusion:

This campaign is a must-have, no doubt about that. It's really fun and beautiful, and all houses are really fun to explore. Another thing I like is that it has a much more eerie and creepy atmosphere than the most other campaigns without being a horror campaign. Clearly deserves a 10.

(had to repost review due to 12.7 rating)

Pros:

Really detailed, good overall visuals and effects
Awesome gameplay
Plenty of supplies, but not too much
Awesome finale, but...

Cons:

... The finale sometimes just gets too much. Common infected keep spawning endlessly in huge crowds at a time, even when tanks spawn.

Bots have a hard time survivng due to lots of small things to walk on, elevators etc.

Conclusion:

A really good campaign with challenging events and overall amazing gameplay and visuals. All the bots ended up dying in the building part in the finale because they couldn't figure out how to climb up and walk on thin wood planks without getting hit by chargers, but besides from the dumb bots it's a really awesome campaign. 9.9/10

Pros:

High quality gunfire sounds

Cons:

Low quality reload sounds
Screeching noises (snd_rebuildaudiocache doesn't fix it)

Conclusion:

The gunfire sounds are pretty good but all reloading and shotgun pump sounds are low quality and have screeching noises. snd_rebuildaudiocache doesn't seem to fix anything at all.

Still looking forward for updates, iwth some improvements this could be really good.

Pros:

Awesome new texture
High quality model
No animation or thirdperson bugs

Cons:

It looks weird how the grip is pulled out
Not a big fan of the walking animation

Conclusion:

This is a really good high-quality reskin for the original M1014 mod. Like always, I dislike the way arby26 makes his walking animations, and it kind of looks weird how the foregrip is pulled out like it was a pump shotgun. Still really good, ends up on a 9.8/10

Pros:

Works correctly, no bugs
Useful
Easy to use in combat

Cons:

No shotgun sounds like always. Valve's fault.

Conclusion:

A really useful script, also doesn't make combat harder because of the camera position. There's no cons, so I can't give it a rating any lower than 10/10.

Pros:

Really detailed and realistic looking
Good atmosphere
Detailed house interior
Big open areas
Not too many ammo piles
Awesome finale battle area
Heavy storms like in Hard Rain

Cons:

If you walk out of the battlearea in the finale, you die
(I was all alone with Rochelle in the end because of it)
No dialogue
No intro or cinematic cutscenes

Conclusion:

This is really a must-play campaign, even though it has no dialogue or backstory. It's really detailed and the gameplay is amazing. The ''deathzone'' at the finale is really annoying though, and the first thing Ellis and Coach decided to do was to walk out there, and I was alone with Rochelle. But overall, it's really fun and should be played if you haven't already.

Pros:

Good atmosphere
Plenty of panic events
Good design
Plenty of supplies and weapons
Perfect length
Custom music
Funny and ''realistic'' safe room text

Cons:

Easy and boring finale

Conclusion:

A really fun and pretty campaign that really looks european. I also really like its creepy atmosphere in the old towers and sewers.

The only thing I disliked was the finale, it was way too easy and tanks barely stood a chance because of their spawn points and the setup of barricades and stairs. Other than that, it's really, really good, and is clearly worth downloading.

(Before I convinced myself that I should download it, I thought it looked a little boring, but clearly I was wrong)

Pros:

Extremely detailed model!
High quality bumpmap textures
Good textures
Good animations*
Extra shell carrier on the body

Cons:

I don't like the way Arby26 makes his walk anims*

Conclusion:

This is an incredible mod for the chrome shotgun, probably the best one I've seen so far. The model is insanely detailed and barely has any squarish circles or lazy details. Another thing is the bumpmap/UV map textures, they really make it look like a real weapon. The only bad thing about is the animation Arby26 uses for the walkcycle, it looks kind of weird. 9.9/10.0

Pros:

Fun when you aren't stuck or lost
Custom zombie sounds
Long
Puzzles
Custom music
Awesome cutscenes
Plenty of supples, but not too many
Multiple paths

Cons:

Extremely confusing
Really easy to get lost
Easy to get stuck
Barely any hints
Bots will often teleport through doors they can't open
Custom models for some weapons. I don't like them

Conclusion:

If it wasn't so incredibly hard to figure out how to solve puzzles, find keys, open doors etc., it'd be really good.

My friends and I had to skip a few parts because we couldn't figure out what to do or where to go. It's really confusing and it's not something you should expect to complete in 10 minutes.

Anyway, I must say that the times we weren't lost or stuck were really fun, and searching through rooms was too.

Pros:

Creepy in the first maps
Detailed
Really dark in the first maps
Traps
Pretty and realistic looking

Cons:

Tanks and Jockeys should not spawn together
Extreme lack of supplies in the finale
Short

Conclusion:

This is indeed a really good campaign, and is one of the few only L4D2 campaigns that can be considered ''scary''. One thing that annoys me is the fact that jockeys and tanks spawn at the same time in the finale, which makes it really hard if you don't take out the Jockey immediately. There's also only a very few throwables and weapons to pick up in the finale. Still, because of the creepy events and detailed mapping, it ends up at 81. I'd love to see more maps of this kind.

Pros:

Good model
Good textures*
Awesome animations

Cons:

The chrome shotgun texture looks weird in some daytime maps

Reloading animation is kind of weird

Conclusion:

Like all the other weapon mods by these guys, it's awesome. Way better than the original pumpshotguns.

Pros:

Good model
Good textures
Good animations

Cons:

Thirdperson holdtype is a little messed up

Conclusion:

This is a really awesome mod for the Kalashnikov AK-47. I'm not the biggest fan of assault rifles and prefer shotguns and pistols, but there's nothing bad about it except for the thirdperson holdtype. No doubt that it deserves a 10.

Pros:

Good textures
Good model
Awesome reloading and firing animations

Cons:

Looks really weird and small in first person
Like the M1014, the walking animation looks a bit weird

Conclusion:

A really good mod for the Franchi SPAS-12 that also removes the weird hook attached to the foldable stock. The animations are good, but again, the walking animation looks a little weird and doesn't fit at all.

Pros:

Good textures
New model / not just a reskin
Goes well with other police/military survivor mods

Cons:

None

Conclusion:

This is a really good skin for Coach. It's really detailed and has no ugly textures or weird stretched parts. Clearly worth downloading.

Pros:

Good textures
Good model
Attachments

Cons:

None

Conclusion:

This is an absolutley awesome mod for the FN SCAR. I'm more a fan of shotguns, but this mod is a must-have.

Pros:

High quality textures
No stretched or misplaced limbs
Custom v_model hands
Equipment is attached correctly

Cons:

Being beaten by a charger looks a little funny (-0)
Way too reflective in daylight maps

Conclusion:

This is definitely an awesome skin/replacement model for Nick. The only thing that could be better is the reflections; In daylight maps or well-lit house maps, it will get all MW2-ish and the half of the body will be almost completely white. Other than that, it's really good.

EDIT: External link doesn't work, the file is deleted.

Pros:

Works perfectly
Useful

Cons:

None

Conclusion:

Unlike the other thirdperson mods I've found here, this is the only one I can get to work. It's really useful and I can't seem to find any bugs.

Edit: forgot one cons, like Dinomite said, none of the shotguns have sounds (even with sound mods installed). Not lowering the rating though.

Pros:

Perfect lenght
You start out only with pistols
Detailed
Lots of panic events
Plenty of supplies
I love deserts

Cons:

Ending cutscene seems buggy
Ending was a little boring (but creative)

Conclusion:

I love that there's so many panic events, it makes it way more challenging and fun. Overall, it's a really awesome campaign that I'm clearly going to play again.

Pros:

Plenty of weapons and throwables
Good lighting
Plenty of opposition
Random screams
Traps, awesome traps

Cons:

Too short

Conclusion:

Edited for update 1.7:

I must say, this campaign is really getting better and better. The new traps and more infected are awesome, the white world models also seem to be fixed. The only problem is still the length, when I played it after the update it only took me 8 minutes to complete it (after being beaten up by the three tanks... holy hell, lol)

If you haven't downloaded this yet, you should definitely give it a try.

Pros:

Awesome shell insertion sound
It looks good with the darkened texture

Cons:

None

Conclusion:

I can't see the difference between the new and old stock and reciever, but the new sounds are good and the new texture is good.

Pros:

Detailed
Lots of enterable houses
Challenging finale

Cons:

The name doesn't fit at all
Too many hordes
A little boring

Conclusion:

It's really good and detailed, but gets kind of boring after a while. It's clearly worth playing but it's not a campaign I feel like playing again.

Pros:

Creatiive
Correct lighting
Good skybox

Cons:

Bots keep falling of the edge
The boss could use some more details

Conclusion:

Even though the boss looks a little boring, it's still really creative and challenging. It also got me the ''Til it Goes Click'' achievement from using the M60 with explosive rounds.

Pros:

Humorous
Easy to understand
Correct lighting
Works in multiplayer

Cons:

Bots won't move

Conclusion:

A really funny and helpful tutorial, but it's annoying how bots won't go with you.

Pros:

No bugs, works perfectly

Cons:

None.

Conclusion:

It's really useful, never breaks and looks good. It's an addon for everyone.

Pros:

Addicting
Challenging
Lots of stuff to do

Cons:

Very simple (all the same texture, etc.)
Bots keep falling off the edge
Special infected spawn out of nowhere
The skybox is literally a ''skybox''

Conclusion:

Really addicting and fun, works well in multiplayer aswell. My friend and I had alot of fun playing this map.

Pros:

Detailed model
Detailed texture

Cons:

Walking animation looks weird

Conclusion:

Really good, worth downloading. The idle, firing and reloading animations are good, the walking animation is the only thing I don't like.

Pros:

I absolutely love the room with the explosives
Correct lighting

Cons:

Elevators can go up/down without everyone in them
Too difficult (objectives, not the infected)
Easy to get stuck
You can't get chest paddles?

Conclusion:

I feel the same way as dgrobinson;

''I gave up because I didn't care about it any more. I don't know if it was just too difficult for my taste. You may like it.''

Pros:

Lots of details
Long
Plenty of interactive stuff
Bowling balls and cones have physics
Massive easter egg
Custom tank models
Perfect finale

Cons:

AI Coach couldn't get on the train (but Rochelle could!?!?)

Conclusion:

A clearly amazing campaign. I had more fun playing this than the original campaigns.

Pros:

Detailed
Creepy atmosphere
Lots of enterable rooms
Plenty of weapons and throwables
Never gets boring
Good loading screen

Cons:

Too short
Easy finale
Not scary after all

Conclusion:

Clearly worth downloading, it's much better than I expected.