XM Digital Satellite Radio- What's the scoop?

I am thinking of getting a tuner but hate the local radio stations, so the new XM radio sounds appealing. After a little research, looks like you can get a sony home receiver for about $299 and the service fee is about $10 per month for 100 nationwide stations and full digital sound. That said, I have had bad experiences with "cd quality" digital radio, for example, Dish Network and DirectTV radio services sound horrible, even when fed through a good D/A converter from the digital outputs of the receiver. The digitial signal is obviously highly compressed prior to the time it gets to you. Anyone know anything about XM Radio, whether it sounds good or not? What sample rate they transmit? Any recommendations or warnings? I apologize in advance for going lo-tech in this forum.