help in buying a ps3

guys i am new to ps3 community ... after using xbox for almost a year i have decided to try ps3 now... not that i am a fan boy or something ... its just that i love gaming ... and living in an era of xbox and ps3 ...i want to enjoy and experience both of the console....


my question is i will be buying a new ps3 320 gig ... now i have herd that only console running at 3.5 can be JB'n....

any idea how can i determine while buying it ??

and one more thing is 320 gig enough ???

i would really appreciate any sort of help people ...


thanks !!!