i need help deciding which one to buy. i can only afford one... actually i can't afford either but i'm gonna buy one of them anyways. my wife is going to be so pissed anyways, i can't decide. i won't have live until after december, and maybe even a few months after december. so i'm looking for good single player gameplay and replay value. also, which one looks more fun to play with friends during a multi-player session? thanks for any suggestions to help me decide, peace.