I've been with AT&T for about 15 years - through all of the iterations AT&T > SWB > Cingular > at&t. Their service is still as good as ever where I live, work and play. However, I am beyond myself with frustration over their policies.
First they have unlimited data. Then they don't. Now, if you have DirecTV, you can get it again, albeit with a butt-load of restrictions and caveats. We currently have 5 lines with unlimited text and talk, and we share 30gb of data, including the option for tethering/hotspots. Since I also have DirecTV service, I inquired about the new unlimited data plan. They will throttle you in congested areas at 22gb and above - so I lose 8gb... and even though it's "unlimited", I cannot do tethering/hotspots.
And I just read that they jacked their upgrade fee from $15 to $20, after previously stating that they were eliminating the upgrade fees for Next and outright purchase of new devices. GRRRRR.
I am tempted to look at T-Mobile, but I've heard some horror stories. Unfortunately, the devil you know is safer than the devil you don't know.