If internet browsing is important to you, you will be in for a nasty shock when you browse on Sprint (I'm assuming you have 4G service--If you don't, you'll still be in for a shock). Sprint does not have a strong 3G network, and their 4G network tends to have gaps in coverage and not penetrate buildings well. And there's no guarantee that Sprint won't go to some kind of bandwidth limits, though I do agree that they'll really try not to do that.
From what I can tell, you aren't happy with the phones Verizon is getting lately (I subscribe to the paranoid theory that they are holding back on the good phones till the get the bandwidth limits on browsing in place), and you are suspicious that you'll eventually be placed on the 2 gig plan. But other than that, if you indicated any other dissatisfaction with Verizon, I missed it.
Sounds like Verizon will be having a few decent phones come out in Summer and Fall, I'd wait it out if I were you. Or you could always go iPhone 4S!
(just kidding)