Anyone Using XM or Sirius On Their System?

I have listened extensively to both in my system. XM seems to have mor band width and be less mid-fi. XM also has a larger play list. Sirius is more compressed and sounds closer to an mp3 download. It doesn't make much difference in the car, but it's very noticeable when doing critical listening. Each also offers some very different program choices, but imho XM is clearly better sonically.