You have to sell your 4 or else what happened to me will happen to you. Your 4's will become obsolete once iOS 5 hits. The thing happened to me when I had a 3g and the 3gs came out. The 3g was 6 months old when I bought it and once the 3gs came out with iOS 3 my phone performed like complete crap. If you have a 4 you have zero reason to be excited about iOS 5. Stick with iOS 4 if you want your phone to work otherwise good luck dealing with a horribly slow interface. I want to be sold on the 4s, but I'm not sold on iOS anymore. It's suppose to a system that can be upgraded and worked on over time, but it is the exact same thing as Android to me. You have to upgrade the hardware in order to enjoy the features. Its marketed that its not like ICS or whatever, but it is. I'm starting to realize that the only difference might be the Apple logo, this cult, and hardware that is a year behind everyone else.