Great campaign

Much better then the canon ones. So good, OMG. 

I hit one bug where I was stuck in a wall in some tunnel, but a teammate shoved me out of it.

Wow

Awesome campaign with many interesting and well-made locations. 
Fun to play, great finale too. Very well made. 

The only drawback is that it is unclear how to stop some crescendo events, like the prison one, or the one in the theatre. 
We had axes, but it seems like you have to pick some magic axe to cut the power line. The onscreen hints disappear very quickly, and then we had no idea what to do.
Also, the part with C4 makes no sense. 

I still have no idea what I was supposed to do in the parking lot with the alarms going off, I just ran away. I could not turn any of them off.
There were some missing textures in the movie theatre (I do have the cold stream missing textures pack!).

Also, it crashed when I had some other campaigns enabled.

A decent small campaign

Cool old-fashioned zombies wearing appropriate clothes..
You mostly fight in the ship interior. Just walk from one hallway to another and melee every zombie in your way. 
It gets old pretty quickly. I wish it had more fun locations, like animated engine rooms, animated boilers, etc. There were some, but it was not particularly fun to fight in those.
 
The finale was super easy (on normal). Just stand on the top and wait for it to end.

No bugs/glitches observed. One corpse got stuck in the staircase and kept bouncing around on its own.

Boring

The campaign has a bit more colour than the canonical L4D campaigns, but it is almost completely happens inside office buildings.
There is no new interesting locations, it is literally room after room. 
No interesting crescendo events.
Most importantly, there is no finale. You just walk into some random looking room, and credits roll. The end.

Great

A bit long and hard (some weird puzzles, etc, I did not play the prequel). Very well made and fun to play. 

The part with jumping on pipes is weird (what are the cars and buses doing there??) and long, but it adds to the overall atmosphere.

Very good.

Very pretty campaign. Felt very easy too. The finale made no sense what so ever, but apart from that it is a very good campaign.

Great Campaign!

Awesome campaign, very challenging, very pretty.

I got stuck in the scaffolding right at the exit from the church at the start, but apart from that I did not experience any bugs. 
It looks like there are no respawn closets, so if you die, you will only be rescued in the next saferoom.