Satellite radio?

My husband wants a portable satellite radio to use mainly in his truck ( a 2006 Toyota Tundra). He doesn't care anything about the MP3 player features - just wants to expand his stations - sports in particular. I don't know where to start as far as brands go. What would look good in his vehicle yet be easy to use in the house or boat also? Another question I have is do I go with Sirius or XM? I have heard rumors they are getting ready to merge. How would that affect things? As you can see, I don't have a clue about this stuff. Please help!