While trying to decide if I wanted a Sirius radio or not I found this link @ bestbuy.com
My wife has an XM radio and she loves it. I liked it as well but wanted to explore Sirius before I got one myself. I took advantage of the three day free trial for streaming music from Sirius and decided the music choices on Sirius were more to my liking than XM. Channels 16 (The Vault) 19 (Buzzsaw) and 23 (Hair Nation) gave me more of what I wanted to listen to. I could not get Raw Dog, the comedy channel on Sirius, to work on the free trial. I have found it to not be as good as XM's adult comedy channel though. I've only heard a bit of Mitch Hedberg and Lewis Black and no Carlin. Maybe it will get better. I don't really give two shits about the Howard Stern switch coming up, but who knows, maybe it will be OK (I doubt it). The NFL coverage was also a deciding factor for me. Just my 2 cents.