DH and I both have it. Only about 5 channels have commercials and I do NOT listen to those channels. But I'm not about to deprive myself of my other favorites. I drive 25 minutes each way to work during school and the morning DJs were driving me crazy (hey, here's our crazy question of the day, morning zoo type crap). I am going on 4 years with mine. One of my prerequisites for a car when I sold the trailblazer was that the car I got would have xm and not sirius--which is why I have a honda and not a toyota.
DH just got a new car receiver (he has a 2002 truck and had to buy an after market receiver). I forget what it's called, but it has some really cool features. If you like a song, you can replay it over and over again. He programmed in our favorite baseball teams and it beeps if there is a game on, and if we don't listen to it the score scrolls at the bottom of the screen. The graphics are much, much better than his old Roady.
The only thing I miss on sirius is radio margaritaville--but you can listen to it online. ALSO, if you have XM in your car you can listen to it online for free--you just have to put in your receiver ID #.
Robin M.