i made the switch from att to comcast about 5 years ago. speed was the issue. price is high as we subscribe to cable, broadband and phone, plus a second hd box in our bedroom, but obviously, you can get cheaper than our cadillac level package. (lol) we've had issues with having to return hd cable boxes and wi-fi modems which can be extremely annoying, but as i live near a sub-station (i know there's another word for it, just can't think of it right now), our speed has always been A+. customer service can be hit or miss, but as long as you can get past the tier one folks, you should be good.
not great, not terrible. you should be fine, imho
not great, not terrible. you should be fine, imho