All I know is I dumped 3 or 4 xm subs (read below, I may still have an account)and went with Sirius. I am a big Howard fan, but I didn't even make the switch to Sirius until the summer. XM's rock music channels suck. It is a fact that they have to pay to play the music, and it is a fact that Sirius invests more money in content> What I am trying to say is I know the bands and songs played on Sirius rock stations, half of the bands on XM are garage bands you have never heard of because they get that music for free. They both suck IMHO when it comes to playing hits, but XM sucks by far the most. Baseball is the only reason to go with XM> Sirius I think has Nascar starting next year, NFL, and NBA.
Ih, If you do go with XM DO NOT GIVE THEM CREDIT CARD INFO! If you go on the vette board and do a search, they are notorious for taking it upon themselves to renew your account because they keep your CC on file. They did it to me TWICE and I had to bitch and moan to Some damn Indian (India) named BOB (yea right) to get a refund. I asked what gave them the right to for them to charge my cars without my permission and he had no answer.