Hi guys, I was wondering what the best firmware for the iPhone 3G currently is, considering some users have brought up battery/laggy issues with OS 4.0, I'm unsure of whether to upgrade from 3.1.3 or not. Can I upload it to 4.1 and jailbreak AND UNLOCK it? Is it worth it? Or will the phone just get slower or lock to the original carrier?? Anyone have any ideas? Thanks a bunch!!