My iPhone 4S is great. Really like the speed boost over the iPhone.

Have had bad experiences with all three iOS 5.0 upgrades though (iPhone 4, touch 4th gen, iPad). The iOS 5.0 installation failed multiple times on all three of them (two were on a 32-bit PC; the other on was on 64-bit PC). The failed at different times in the process. On two devices, all app and folder info were lost. These were by far the worst Apple iOS upgrades that I've been through.