hey there ... Ive become quite bored with my travels with my iphone 3g 05.11.07(waiting on my ip4)and just have a question . I was on 3.1.2 jb with blackra1n but then got bored recently and restored to fresh 3.1.2 because i wanted to try the jb with jailbreakme. Now noticed ever since i used jailbreakme cydia is slower than ever and sb keeps crashing and become bothersome. I know i should just restore again but think the results will be the same... What im lookin to do is upgrade to 4.0.1 just for giggles and if i dont like it go back to ither 3.1.2 or 3.1.3. Yes i know the ios4.0.1 is going to slow me down yady yadda but cant be any slower than it is atm lol and seems most themes and that are bein made are for the newer ios's ... So with that said is this still possible to upgrade and downgrade back on the iphone 3g or will my curiosity kill me ? And if so can i be pointed in the rite direction ! In my search ive seen a few different options and just want the best way possible thanks in advance !!