I have a Sprint iPhone 4S. It has a few deep scratches on the back and the oleophobic coating has worn off. It has AppleCare+ until November. I'm planning on switching to AT&T so I won't be able to use this one, even as a backup phone (do people still keep these?). I called up Apple to ask about getting the back replaced and they said they couldn't but I could use one of my AC+ claims and get a refurbed one for $50. Would this be worth it as far as resale value goes? I know Sprint is losing some customers and it's not 4G, so that hurts it, but it's still a solid phone. Or would I be better off just selling it as is? I will say that not having the oleophobic coating is annoying.