Pros:

Very original and fun
Many campaign mods make it interesting to replay
popularly played online
full of exploration

Cons:

The finale needs a bit more beauty (add mushrooms?)
Sometimes glitches L4D2 and has to be uninstalled before going online ("enforcing consistency")
nether chapter is very confusing, and is very easy to get lost in.
no versus?

Conclusion:

Very good, and it is surely one of the best campaigns out there. It does have a few bugs, but it truly deserves its reputation.

Pros:

Great color choice
Fits Ellis pretty well

Cons:

Can't think of any

Conclusion:

Pretty dang good! Nice coloring, fits Ellis...great skin you got here!