My first cell phone was with Nextel, then Sprint, then Verizon, then Cingular/AT&T. I wasn't that impressed with Verizon's service at the time. I went with Verizon because they had a Windows Smartphone. Once Cingular was offered here, I switched. I've had less dropped calls with AT&T. I live in Virginia Beach and work in Norfolk. The coverage at my house isn't as strong as it is in downtown Norfolk, but I still always have a signal. I work on the 19th floor of our building, and I get an excellent signal.
When I've dealt with AT&T's customer service, I've been impressed. My old phone was the SMT5600, and it failed on my a few times (refurbished phone). They always overnighted me a replacement. Sometimes, it's who you talk to at the time. I was very happy when the iPhone came out on AT&T's network.