I have had Dish for 8 years or so (maybe longer). We have had great experiences with them. If we had an issue they were here the next day. Which was only twice, once was to replace old wiring in our house that went bad and just recently we had to swap out a DVR that went bad. They sent a new one and a shipping label, it was very easy.
For what I get (which is just about everything they have in English) the price has always been lower than when I compared it to Direct TV. My parents have Direct TV and from what I can see it looks like they overpay.
I have never had AT&T.