Pros:

Great layout
Good final
Just amazing

Cons:

Can't think of any

Conclusion:

I was one of the first to play the l4d1 version and me and my friends loved it. We also loved this one with all the little extras added in. Love the Portal 2 and Doctor Who easter egg.

Pros:

Super fun with friends
Good map for a few laughs

Cons:

If it's your first time you will die a lot

Conclusion:

Me and One of my other friend always try and get people to play this. I know some might find it dumb, but we find it very fun. Which a L4D2 version would me made.