I had AT&T for about ten years and changed to Sprint in 2010 due to price and the fact that Sprint gives you more. I had zero complaints until four months ago. I always had good call connections and while their internet isn't the fastest it was always constant and operational. So I got a notice that they were going to start upgrading the towers in metro Detroit and it's gotten unusable at times. Yesterday while in an area where there is always three bars or more of signal I dropped a call 9 times. I was outside. There are also areas where I have signal and my iPhone 4 says 3G, and there will be no internet at all. Yet they refuse to credit my bill.