I apologize, I am sure this question has been asked numerous times, but I want to make sure I don't screw this up... I have a 3GS that I am getting ready to sell, and I want to erase all of my data from it. It currently has the original baseband (4.26.08) and is running iOS 4.3.3. Unlocked and jailbroken. I would like to erase all of my data, and upgrade it to iOS5, if possible, but making absolute sure I keep the unlock available. Can someone kindly point me in the right direction? Thank you in advance!