Pros:

-very good detail
-nice new models
-good original panic event on map 4
-the final is just "incredible"
-no big bug
-a good challenge

Cons:

-fps issues on map 1 3 5 (radeam 5770)
-not enough ammo or weapon on map 2 and map 3
-all maps are maybe too long (especially for a versus mode)

Conclusion:

It one of the best custom campaign i have payed on left4dead2.
it's more than a left4dead2 conversion, your job is fantastic.

keep a good work