Should I get the PSP Go or an XBox 360?

Hey, I was wondering what you would get, an xbox 360 or the psp go. I already have a 360, I had it since Christmas 2007 but it freezes occasionally so I know it's about to get rrod. I was also wondering if I should get the elite or the custom 250gb MW2 360. There's a lot of games I also want for PSP (Dissidia, Gran Turismo, MGS, Soul Calibur), but I bought 11 games this year for my 360, and I won't be able to play them? Please tell me which you would buy.