Pros:

"whats this button do"
Interesting
Creative
Mind-Boggling :)

Cons:

"no not a set of witches!"
Finale seemed bugged at the car. Or is it true there arent supposed to be mobs anywhere near it?

Conclusion:

Loved it! I am always a fun of puzzles and mazes and TONS OF HORDES! Fun campaign! Even better with friends.

Pros:

Retro!
Fun!
Entertaining!
Quite custom!

Cons:

Got stuck a few spots but nothing major  (tank threw me and I got stuck)
Finale needs its own level lol

Conclusion:

Very fun! Very good

Also on the last part after the custscene (when l4d2 finale music starts)  I was like OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO S***! When it ended a horde was right infront of me. 

Pros:

Good detail towards the last 2 levels.
Its the titanic...

Cons:

Very small hallways.
Maze-like hallways - some just go into blank dead ends.
If you cant sink it, blow it up! Lol
Textures repeat, items repeat a ton! Gets really dull.

Conclusion:

I was VERY VERY VERY depressed that I didn't look overboard at the end to find a floating door with a dead zombie hanging onto another dead zombie!!!!!!!!!!!!!

Pros:

My fav campaign but in dark, creepy atmosphere
Fits just like the original
DARK

Cons:

Some say its too dark, IMO its night time and its supposed to be dark. 

Conclusion:

Love it

Pros:

Great detail
Different environment - close quarters and many areas to go into
Loved the cable car event(s)

Cons:

Too many routes

Conclusion:

Loved the detail so far in the released maps. However I felt there was actually too many areas to get into and eventually started going "Well I have no idea if this is the way but lets see where it goes!"

Pros:

Original planning like QE1.
Fun
Puzzle-like
Makes you think

Cons:

Too much grenade launcher "work"

Conclusion:

My friends and I loved Questionable Ethics 1, even played it many times and almost killed each other in real-life while attempting it on expert. QE2 (beta) continues with the same gameplay style as the first did and gives you a few laughs with it as well.

The only thing I did not like so far in the beta is the grenade launcher and the targets. Couple of reasons. The first, some of the targets were kinda glitchy. The first one (I think - whichever was the one above the drop down gate that falls and alerts the horde) took around 10 grenades to activate it (and at least 6 of them were direct hits). And another reason is that I play most of my L4D2 on Expert and the grenade launcher is a deathwish when it misses. Lastly, if you play the campaign by yourself - you will then almost need to carry a grenade launcher at all times since the AI cannot. Since I prefer to carry my automatic, I cant say I enjoy carrying the grenade launcher. lol 

Overall - great campaign!