I only own a couple 360 games so far (Left 4 Dead, Burnout Paradise) and have been renting through GameFly, but I'd enjoy actually owning a few more games. I'm concerned about gameplay length and replayability (not necessarily including online). I'd rather rent a short solo game like Price of Persia (which is just what I did), but if a game is longer like 15+ hours, might be worth a buy. Some considerations: - Dead Space - Fable II - Call of Duty 4 or 5 (is the online really good or too filled with wankers?) Already have Fallout 3 for PC and was going to play the PC version of Mass Effect too since I hear it's a little better. Not interested in Gears 2 or Halo 3 just yet. Might get Halo Wars if I really like the demo, but that's not out yet. Thoughts?