We have been with ATT for 9 years without problems. I have found their tech support for internet to be excellent and the cell phone does what I want when I want it, no problems. No reason for me to complain. Years ago, because of my wife’s employment we had Sprint, couldn’t get way from them fast enough.
I’m fine with AT&T, for me Verizon is the devil. I was okay with them until one day my home phone stopped working. I called them up and it turned out that they had just bought MCI and they had discovered an old MCI bill that I hadn’t paid. Which led to an hour of tranfer hell where no one could find the alleged old bill (which I was perfectly willing to pay). It was easier to just give up my land line than deal with the nonsense.