Im taking my iphone 3g in for a replacement on tuesday night. They are going to exchange it for a "new" refurbished model. Since my current iphone is dying every 30 mins or so, and has dust under the screen. Do you think if i asked the genius instead of giving me another 3g, if i can pay an extra 200 for a 3Gs? Would this work? Or would they deny me for no reason?