I've tried several and ended up back with AT&T. You get what you pay for and AT&T is pretty good at what they do. I've tried Comcast several times, left and went back and it just did NOT please me at all. The customer service was horrific for me and the service itself wasn't real great.
I've got AT&T's U-verse service now and it's great for me. In short, there are some fly-by night outfits offering service but just be prepared for the hassle of your life if you go that route.