Pros:

Good port.
Decent options of where you can stand for the finale.
Crowbars everywhere (my Freeman senses are tingling).

Cons:

A few bugs.
Very easy, especially the finale.

Conclusion:

Bugs I noticed: 
On the train tracks, zombies would go on the left side of the stationary trains and just stand still between them (despite no invisible wall).
When reaching the bottom of the elevators and reaching the walkways, the tank and other infected couldn't get up to the walkways, despite there being a way up.
The tank can get into the train in the finale (not necessarily a bug, but it's inconsistent with what other campaigns do).
If you jump straight into the vat of water you die instantly (even though it's quite a short drop into water). If you jump on the rim of the vat and then the water, you're fine.


Overall very enjoyable. I do like seeing the HL2 maps made into L4D campaigns, and it's good to see them done well. Might've been cool to see some evidence of Grigori being there. I'll definitely play this again. It was certainly well done.

Pros:

Original. Very original.
Hilarious when playing with friends.
Items in boxes.
Only bug was a texture problem at the finale.

Cons:

No versus.
Running past another survivor on a thin ledge tends to push them off.
Finale was really easy, while the chapter before the finale was quite difficult.

Conclusion:

Loved this map. We had so many laughs whenever someone fell off. Would love to see a versus mode for this.

Pros:

Original, mostly.
Glowing green directions allow for simplicity with a complex system.
Lara Croft.

Cons:

The running around doing stuff was rather tedious.
A number of things stayed green when they shouldn't have.
Invisible walls everywhere.
Easy to get lost.
Finale kinda boring. Also quite easy if you have a molotov or two (I expected to have to run to the smaller speed boat off to the side).
Chapter just before it would've made a better finale (why get back out of the helicopter?).
One player who died on the chapter before the finale didn't spawn in the finale.
Layout didn't make a lot of sense. Had to use the electricity to open glass doors. Also why the medieval town and why were there two windmills in a place you wouldn't put windmills. Took away from the immersion.

Conclusion:

First few chapters were good. Last one was far too boring, though. I give this a relatively high score though, as it could've been much worse.

Pros:

Everything's new. Everything unexpected if you haven't already played it.
Original.
Loved the idea of things being in boxes.

Cons:

AI cannot target enemies or avoid explosives. Makes the ripper difficult since only you are chasing him.
Rather inobvious when certain things hurt you and they can also hurt the bots and they'll do nothing about it.
One or two bugs.

Conclusion:

Gave a practice run of the first few chapters on single player before playing it with three friends. Damn funny if you play with other people. Especially when unexpected stuff happens.
Bug-wise I found that the zombies in the Ripper section ran to the blocked up wall and just stayed there. Might've been because one player who had died had spawned in the wrong safe house, at the other end of the map. This didn't happen on single player.
Otherwise, quite enjoyable. Vs. should be fun with this.
I'll give it a 93 because it's not too buggy, considering it's drastically different to the official system. On top of that it's rather enjoyable. Most of the fun comes out of the first run-through though, so reruns of this campaign might get boring.

Pros:

No bugs that I saw
The map seems spot on

Cons:

Just on bit where you fall through somewhere and there's just a lot of smoke. Smoke added a little lag. Hardly a major problem.
Was hoping to see some combine or civilian corpses or zombies.

Conclusion:

I loved city 17 in HL2. Probably more fun to do in L4D2 though. I'm giving this a 96 because I thoroughly enjoyed the map that I mostly recognised.
No real cons either. I'm glad someone's ported the fun maps from other source games to L4D2. Would definitely like to see more.