Looks like XM may be the better choice.
Coke or Pepsi? Choose your flavor.
Because new car or home users have a choice in satellite radio, it's worth examining Sirius and XM Radio a little more closely. Both systems are only available in the continental United States and offer parental control to block stations with explicit language. Both offer music in a commercial-free format, talk radio, and national news networks.
XM is more established. They started broadcasting in September 2001, offer 101 channels, and currently have a subscriber base of over 2 million. General Motors and Honda back XM. The majority of XM's studios are located in Washington DC. The XM Radio network consists of two geosynchronous satellites and repeaters in major metro areas.
Allen Goldberg, Director of Corporate Affairs, XM Radio says "XM takes the best from FM radio and improves on it." Goldberg also feels that the on-air personalities at XM are more professional than those on Sirius.
Sirius is newer to the game. Their first broadcast was in July 2002, and they have a paying subscriber base of less than 1 million. Sirius' studios are located in New York City's Rockefeller center. They have three elliptical-orbit satellites and fewer repeaters than XM Radio.
Vice-President of Communications at Jim Collins says Sirius' advantages include more original programming, no commercials on any music channel, and better satellite coverage allowing Sirius to be less repeater dependent.
Regardless of which flavor you choose, the programming is remarkably similar. However, there are differences. If you are a home user or are buying a vehicle that offers choice between XM and Sirius, take a look at this chart to see which service has more stations you desire.