I just bought an unlocked 4S yesterday for $549 at my local Apple store, when I noticed the lower price online (it's back up to $599 today) I'm upgrading from a jailbroken 4 that I use on tmo. Everything about it is great, including iOS 6, except the calls sounds terrible on it, with Bluetooth or by itself. Muffled, and hard to hear. I don't know if i got a lemon or what. My 4 sounds perfectly fine, so it is not a tmo network issue. I got the 2yr warranty, so I'm taking it back tmrw, hopefully for a return on the original warranty and not my extended, since you can only use the extended a couple times before they stop replacing the phone. Any experience with a bad sounding phone?