Pros:

-A very fresh addition to L4D2
-The Occasional Visibility Blocker is far better then any other one i have seen so far (including Valve's Hard Rain)
-The ability to upgrade your base makes this game endlessly fun
-The game truly does get harder and harder as time goes by, even with upgrades.

Cons:

-The ai are stupid

Conclusion:

This survival map is a 'must play' for all L4D2 survival fans! The only bad thing was when I was playing with AI's. Once they were smoked or smacked outside the wall, they never came back and inevitability died. Though once i played this map with 3 other friends, that problem immediately disappeared (i wonder why?). In the end, Outpost2 has quickly become my favorite thing to play in L4D2. I keep trying different combinations of upgrades and the fun never stops. This map deserves every point of the 100/100, and I do not hesitate to give them to you. Good Job Reaper!