Great writing.
Challenging gameplay. - If you mean frustrating at times yes exactly.
Gives around 5 to 9 hours for each playthrough.
Yeah I'd say it's pretty good.
It can get a bit hectic at points finding something. Everything feels like a maze and beeping collars, ghost people, traps, and Red mist don't help either. If your into thrillers this is for you. Writing is wonderful(This is all I can say, because if I get into it I might spoil it for you). And if your in Survival Mode prepare for an aggrevating playthrough. Only thing I hate about the DLC is the pure feeling that I'm being rushed to find things and I feel I don't get time to explore until the very end when I really want to leave.
Rewards are great though, but they are gamebreaking in a way.
PS PeterF its called the Automatic Rifle(The BAR like light machine gun your talking about right?), the Battle Rifle would have been the M1 garand type weapon but I think they cut it during developement. This Machine was supposed to the unique variant while the regular ones were to be called battle rifles.