The post jb os is stable, no worries there. that said, its like anything else. There will be an app out there that wasn't developed right and the phone won't like it. Your phone might reboot in safe mode. Turn it off, turn it back on a couple of times until you see the gp icon and things are good. not really much different than stock if you ask me. most of the time and somtimes rightly so if the device starts acting wonky (technical term) and the user has jailbroken or rooted is your on android they will blame that instead of a bad app. If you do your homework, look at the ratings and or check out the feedback on forums like these chances are you will be good. And when you jb, remember when you plug into itunes, DO NOT CLICK UPDATE, HIT CANCEL