Both Batman: Arkham Asylum and Batman: Arkham City are 75% off on Steam right now. I've only had a little bit of experience with Arkham City; that's the extent of my playing either game so far. I am going to buy one, and I only have enough in Steam to buy one - so I'm looking for recommendations. Arkham Asylum is a couple dollars cheaper (leaving the possibility open that another game comes out on a deal that I can pick up) and it's the first one - otherwise, I don't see any reasons to buy one over the other.
So, I'm asking you folk.