I have a new iPhone 5 waiting on me at home. I currently use a 4S and my wife uses a 4. My 4S is JB. Her 4 is not. I'll be swapping to the 5 and will be giving her the 4S and selling the 4. When I erase all data on the JB 4S will that wipe the JB and put it back to factory? I would update it to iOS 6 and she wouldn't use any of the JB features. My other question is around how best to swap devices for a clean start? Backup to iCloud and erase all and setup as new then restoring from ICloud? Thanks.