I have been trying for a couple days to figure this out myself, but I think I need to ask some questions to make sure I do this right. I haven't been around in a while here.. I have a 3G on 3.0 with firmware 4.26.08. I am jailbroke and unlocked (redsnow and ultrasnow). I have no official SIM and am using T-Mobile. I would like to update to at least 3.1.3 because so many apps require it now. Of course, since I will be re-jailbreaking and unlocking, I would prefer an even more current OS if possible. I see the jailbreak of 4.2 is still in beta. Will I be safe upgrading to 4.1 on the 3G without compromising speed and other things? If so, is it best to use redsnow in my situation? Should I use the latest version from the DevTeam with the new improved hactivation method mentioned on a thread on this page? I assume I still unlock with ultrasnow? Thanks in advance!