Hello, I was told by AT&T to restore the device to complete the unlocking process. When I try to restore in iTunes, I'm informed that iTunes will restore and upgrade my iPhone to iOS 4.2. I've read everywhere that iOS > 4.0 slows up iPhone 3G. So, I'd like to: 1. Restore my phone and get it unlocked. 2. Run iOS 3.1.3. Will following this guide accomplish my above goals? http://lifehacker.com/5572003/how-to-downgrade-your-iphone-3g[s]-from-ios-4-to-ios-313 If not, could the experts here please advise on how I should go about doing it? I'd really appreciate any input on this. Thanks a ton in advance.