Before the XM vs Sirius goes too far I think it's fair to say they both have their merits. I think Sirius is a better overall service though. I had XM from the beginning and I was rather annoyed with the amount of "searching" I had to do to find a song I actually liked. They do play a deeper playlist but it seems like mostly songs that I didn't like when they were new. I think Sirius has MUCH better rock playlists and stations. There are just too many variables in user taste to say one is better than the other for everyone. I wouldn't put too much weight into the stock price. They both seem to rise and fall at the same rates. It will be a couple of years before it's clear if one will ever out do the other. Also, remember that XM had a year head start. I currently subscribe to both services.