Can't commnet on XM, but I've had Sirius in my car since last March. (I'm pretty sure the sound of the two services is comparable, since the technology is similar, if not the same.) Sirius is great. You either get the signal - very clear, no static - or you don't. Drop outs are *very* infrequent, especially in larger urban areas, which are served by ground repeater stations. Regarding sound quality - far better than any AM I've ever heard - - and most, but not the best, FM.
In terms of choosing between the XM and Sirius, check out their websites and make your choice based on programming. (I chose Sirius because I listen mostly to jazz and classical, and I (slightly) preferrred what I heard when I compared the offerings of the two on-line.) At the time, XM had some commercials on its music channels and Sirius music channels were commercial-free, and this was also a factor in my decision. As of this week, however, XM has announced it too will offer commercial-free music channels.
Price-wise, Sirius is about $13/mo., while XM is only $10. Still, the price differential is insignificant, and you should make your choice based upon whose programming you prefer. Whichever service you select, I'm sure you'll love it!
In terms of choosing between the XM and Sirius, check out their websites and make your choice based on programming. (I chose Sirius because I listen mostly to jazz and classical, and I (slightly) preferrred what I heard when I compared the offerings of the two on-line.) At the time, XM had some commercials on its music channels and Sirius music channels were commercial-free, and this was also a factor in my decision. As of this week, however, XM has announced it too will offer commercial-free music channels.
Price-wise, Sirius is about $13/mo., while XM is only $10. Still, the price differential is insignificant, and you should make your choice based upon whose programming you prefer. Whichever service you select, I'm sure you'll love it!