Hello again all! Quick question. I had a 3G and I know you can unlocked it on whatever firmware you have 3.1.3 4.0.1 you know whatever but I was told if I have a 3GS I might not be able to jailbreak/unlock IF i had a certain bootrom? Think thats it. Anyways, Question is CAN I UNLOCKED ANY 3GS? no matter what; meaning I dont have to check if its old bootrom or what the firmware is

Can I downgrade a 3G from 4.0.1 or 4.0.2 to 3.1.3. A 3G on iOS 4 is SO SLOW I rip my hair out just getting to messages. Thanks in advance for help