I see a lot of discussions about this but I don't really understand it. Most likely because I've never bought an un-subsidized phone before. What are the benefits of buying a phone at full retail with no contract? I understand ur not locked into a 2 year commitment but if I'm staying with the same carrier I'm still going to have to pay for service...right? So I walk into AT&T and pay $600 for iPhone with no contract. What do I do next? Do i pay the same monthly fee that I would with a contract? Same data rates? Texting plan, etc? Other then not be locked into AT&T for 2 years, what difference does it make. I know a lot of people do it, so I'm sure there's a good reason, but I just don't understand. The way I figure it, it would wind up costing more money doing it that way. I equally don't understand how I sold my 16month iPhone 4 in decent condition (but not perfect) to someone for $400. I know some do it so they can unlock and use on other carriers but even that seems not very beneficial. Can someone spell this out for me. Thanks!