I bought the IP4 on opening weekend, and every source in Dallas was sold out for walk ins, except for a single Walmart. The phone has been so-so except for a serious problem with the proximity sensor(it does have the signal attenuation problem as well, no surprise there). While I am talking on the phone, the screen will randomly come back on, and inevitably some buttons get pressed by my cheek. Sometimes it just activates speakerphone, which is embarrassing, but often it hangs up on the person. I have had at least one call get disconnected every day, sometimes it has happened 5 or 6 times in a row on a single call. I have been in contact with Apple Support, and they have acknowledged that it is a pretty common problem, but we haven't discussed my options. The case is still open. I have read about many people on here who have had their phones replaced due to the same issues, and I really would like to try my luck with one of the more recent build date phones. My question is this, would I be able to return my phone through the Apple Store even though I didn't purchase it there, or would I be forced to go through Walmart? (This is something I want to avoid, if at all possible) I have about a week longer until the 30 days is up, so I need to act quickly. Anyone have any experience with this?