Pros:

-Randomized traps and puzzles.
-Forces bots to enter elevators, tunnels, etc. expediting the process to making it through the puzzles.
-Excellent gameplay.
-EPIC finale.

Cons:

None.

Conclusion:

So many times during this campaign I was blown away by the insanity. There are a lot of "what the crap just happened?", and "ooooo, what is that?" moments. It's not the sort of campaign where you just run and shoot, you have to think if you want to survive, but the director doesn't let you sit still for long. Playing with others is definitely a must, you could probably do it all by yourself, but it would make it much more difficult. It somewhat reminds me of the "Powerstation" campaign. Thanks to the randimization of most everything in each map, I'm sure my friends and I will be playing this a lot.

All in all verdict: EPIC CAMPAIGN IS EEEEEEEEPIIIIIIIIIIIIIIC.

Pros:

GARRUS!
Perfectly detailed
Good animations
Includes GUI stuffs (icons, incap pic, etc.)

Cons:

Hands look funky while holding pistols.
No first person hands (still Ellis hands)
No face posing (mouth doesn't move)

Conclusion:

Best Ellis replacement by far. I loved Garrus in ME and ME2 and it feels good to have him on my team again in L4D2!

Pros:

HOLY CRAP I CAN USE THE VOICE CHAT AND THE CHAINSAW AT THE SAME TIME!!!!!

Cons:

NOTHING.

Conclusion:

If you are tired of not being able to hear people telling you to duck while using the chainsaw, then download this.

Pros:

Very detailed. Looks good, even at max graphics settings.

Cons:

No first person hands.
No gui stuff (incap pic, etc.)
Addon name is just "replacement for Coach", should be changed to "Master Coach" or something!

Conclusion:

All around good.
I messed with my copy and added some gui stuff (incap pic, etc.) and changed the name of the addon so I can tell the difference between it and Mr Lanky's other Coach replacements.