XM also has much better hardware.  They are at least 18 months ahead
 (or more) in their chipsets.  Unless one wants to listen to NFL games,
 I would choose XM.  I think some younger people may prefer some of the
 music on Sirius, though -- I can't listen to it, personally.
Doesn't Sirius also have NPR?
That plus the NFL could be a deciding factor for me.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"