Pros:

The Portal 2 Easter-Egg, the best Easter-Egg in a game;
Skin for the tanks of the Chapter 5;
The exclusive sounds and musics of this campaign;
Scenario;
A new melee weapon, found in the stadium;
Long Campaign;
Enough zombies. 

Cons:

Shit, i didn't have any cons to say.

Conclusion:

Awesome Campaign. Masterpiece. i'm impressed with it. At the first look, you think it's a Valve's campaign, but isn't. This Campaign is the best custom map ever made for Left 4 Dead 2. I Recommend this for the guys who love the L4D games and the Portal 2 Game (Because of the Easter-Egg). They will love it.