Questionable Ethics Kinda Feel.

Pros:
 - random routes
 - visual and verbal cues
 - ample supplies
 - good shooting angles
 - good shooting angles!
 - and very good shooting angles! haven't felt so good killing zombies for quite some time.
 - smart tricks and traps that add to the fun of the experience
 - reasonable hordes and tanks
Cons:
 - almost none.
 - apart from may be just some more rescue rooms