Pros:

The witch actually now FITS somewhat more in the L4D2 campaigns now with this skin! What do you know!
Appears to be more advanced in infection with hair loss, more sharpened and dark claws, and an overall bloodier look from so many accidentally startling her and not living to tell the story.

Cons:

Makes her fit in more with Common Infected, making her harder to spot. But I don't really mind that.

Conclusion:

Why didn't Valve make a new skin like this for the which when they were creating L4D2? That's the only thing I'm left to ask while staring at this nice model in-game. Definitely recommend downloading this for those who feel the witch is a bit "out of place" with her original model.

Pros:

It's the infamous Chicago Typewriter, who doesn't love it?
Reload sounds of the AK-47 fit nicely.
The stock/box magazine makes it fit in much more suitably with the other guns than the standard drum magazine. It also doesn't look like plastic!
Accurate design and tone help make it feel as if it was a part of the original game.
Not too shiny or glossy helps it fit in even more with the other guns, a feature the drum magazine alternative addon unfortunately suffers from.

Cons:

No sounds that are included.

Conclusion:

 Although I still use my drum magazine Thompson over this one, I find it the superior of the two with it's authentic grip, look, and animations. Give both a try and see which one you prefer over the other, unless you want to routinely switch between them.

Pros:

It's the infamous Chicago Typewriter, who doesn't love it?
Reload sounds of the AK-47 fit nicely.
Accurate design and tone help make it feel as if it was a part of the original game.

Cons:

No sounds that are included.
A little bit too shiny and glossy, it seems to stand out.
The drum magazine seems to appear too much like plastic in first person, and clashes with the shiny, glossy look of the rest of the weapon.

Conclusion:

Only two cons, but this is an excellent recreation and replacement for the AK-47, although it is technically NOT a submachine gun, while the Thompson is.  Still, I recommend this for those who are fans of gangster/mob/mafia and trench warfare weaponry.

Pros:

Corrects the sound so we do not have a common case of one gun sounding like another.

Cons:

Sounds a bit quiet for the Tommy gun.
Randomly during a campaign or map load up, the gunfire will often at time have another soundfile conflict and sound immediately after. This is annoying as the sound will be at a higher, faster pitch, and it is only worse considering the Thompson is a machine gun.

Conclusion:

Until the sound issue is fixed, I really do NOT recommend downloading this mod, unless you can tolerate high, squeaking sounds.

Pros:

Finally, always loved the shotgun that brought me into the world of... well, guns!
Brings more of the original feel of the first game into the second, especially when you play the original campaigns.

Cons:

Wrong sound when firing.
Pretty sure it is somewhat small.
Pretty sure that was not the animation the original gun had in L4D.
The pump is not pumped when it is reloaded...

Conclusion:

I was estatic when I saw this at first, but after downloading it, I have mixed feelings for it... it has the wrong firing sounds, seems like it was not properly sized when it was ported, the animations seem wrong, and the pump not being pumped when you reload it... that just seems criminal to me. Giving this a 5.6, this definitely needs improvement.

Pros:

Continues off quite nicely from where the first campaign ended.
The dialogue placement and selection was great, even if a few of them were recycled.
Has even more increased detail in the various environments compared to the first Questionable Ethics.
Puzzles involving the Grenade Launcher were ingenious and unique; quite refreshing and gives you a reason to have at least one person on your team to hold a grenade launcher at all times.
Bots navigate the maps quite impressively, excluding the problems in Chapter 2 & Chapter 4 I point out in my Cons about the map.
Random pattern of the various weapon, item, and painting spawns are guaranteed to give this map re-playability to many: Including those who love getting "surprises"!
Finale mixes both old and new; traps and puzzles from both of the campaigns are featured, albeit reused and tweaked to be somewhat different.

Cons:

The Grenade Launchers on certain servers are replaced instead by M60s; this is especially bad when they replace the first set you encounter at the beginning of Chapter 1, rendering the campaign unplayable since only the Grenade Launcher can shatter the glass.
The bots have a horrible tendency to easily fall and hang off ledges in both the crescendo event in Chapter 2, and the large fire pit that you have to ascend in Chapter 4.
The campaign is unbeatable in Single Player unless you start from Chapter 5, which sadly means you skip directly to the Finale. The reason is  because Chapter 4 features a puzzle which requires teamwork that involves two players in two different rooms shooting two targets quickly in a short time span, requiring the second to be shot not long after the first one is shot; otherwise, the one that was shot first resets, requiring you to attempt it again. Due to the short time you are given to shoot the other target, it is impossible to simply run back to the other room and shoot it to complete the puzzle alone.

Conclusion:

Besides the few Cons I mention, this map is possibly one of the most creative and fun maps I have ever downloaded and played through. The various puzzles, traps, gauntlets, and crescendo events were all enjoyable to the end, my favorite being the gauntlet with the cars dropping into the fire pit that you must ascend in Chapter 4. All in all, I give it a 9.7; 10 would have been given, if it wasn't for the few gripes I had with it.