@matigo I bought through the iPhone Purchase Program last year, and have mixed feelings. It generally went well, but I wish I just got a bill every month instead of charging my credit card. And I'm not upgrading this year, so I can't comment on that part.
That said, we'll be getting my wife's new phone through Verizon, because it works out better for our current situation. And because my iPhone came unlocked, I'll be porting mine to Verizon while we're there, so that aspect worked out well.