Baseball is the only reason I would consider XM.
Music sounds absolutely awful on XM. Every song sounds like a low-density MP3 file. I'd guess Sirius is the same.
Actually, I love the sound of music on Sirius, although I bought it almost exclusively for the NFL and Texas Tech basketball.
I've had both.......i had XM in one vehicle as OEM and it sounded great.
my new vehicle has a sirius aftermarket unit (FM Modulated)and it sounds awful....more like digital AM.
You can get a season pass to all MLB games on the radio for 14.95. They are archived until the next season. Go to MLB.com to get it. It is a lot cheaper than XM.