I'm switching to Ting, and just ordered a used Samsung Galaxy II (I have a version older than that, now) for $265 or so. Due to the $ I'll be saving by switching from US Cellular, I'll have that paid for in savings by the end of the year.
Note: I did really want the new Galaxy IV, mostly for the (OMG) 16MP camera. Until I did some research and found I could buy a 16MP camera for under $100, so could get the Galaxy II AND a 16MP camera for less than the price of the IV. We don't have 4G here, so that's not even a consideration for me. I haven't bought the camera, but just knowing I could is what talked me down from the IV.