Works fine for voice, and usually good for texts ... sometimes they're delayed a bit going out. I haven't really tried data but once (to check radar, I think) and that was inside club level and it wouldn't work ... might have been the structure.
I have two phones with a total of 1400 minutes on the Family & Friends (10 of 'em, so I never use my monthly minutes), unlimited text on both, and 2 GB data only on one and the total, including taxes, is about $145. And that's with a 15% discount. I think the data part is about $30.
I used to have AT&T but it got to the point where I had no signal at all at my house. I switched to Verizon, which is a bit more expensive, about 3 years ago and have never had a problem getting a signal anywhere I go and have never had a dropped call. There's about a 20 mile stretch near Hamilton, AL, where I get no signal at all when I travel to MSU, but that's the only place I've ever encountered that. AT&T was dead in the same place. I have an iPhone 4S, which is only 3G, so I can't speak to Verizon's 4G service.