I currently have jb on 4.1. my iphone springboard crashed twice since JB 4.1 was out. I am thinking of starting fresh and restore 4.1 from itune and jb again. if I don't restore 4.1 now, it will be gone from itune this sunday (don't trust restore from download elsewhere). beside 4.2 JB might take a while to be available. should I do this? if not, why?