As for performance, we found XM to have the more consistent, reliable signal of the two. The sound never faltered, and there were no silent gaps as we drove around in XM's Cadillac, while Sirius occasionally had dead zones that caused moments of interruption in their signal. It should be noted, however, that Sirius launched its nation-wide service last week, and company executives say momentary glitches should disappear as they work out a few bugs.
Another problem -- as satellite radio settles into its infancy -- is, simply, getting it. This is a new technology and not every salesperson out there is familiar with it. We stopped by Best Buy and Tweeter, two places that sell a lot of car audio equipment, and the salespeople weren't well-versed in the technology.
The sales rep at Best Buy wasn't sure if we needed an antenna. Over at Tweeter, they seemed unsure and apprehensive about answering questions.
For those who are patient, the best option might be to wait until new cars offer standard and satellite radios. General Motors, for example, has announced that it will be offering satellite radios next year in 25 of its car models.
What the future holds for the two satellite radio companies will be interesting to watch. While the technology is terrific, the public is likely to have an initial adverse reaction to radio that comes with a price tag. Already, both companies have faced some tough financial issues -- XM saw its shares drop 22 percent this week after stock analysts downgraded its ratings.
As satellite radios become more prevalent in new cars, though, public acceptance might follow. Even for $10 a month, satellite radio is a welcome alternative to the scant, static-interrupted selection we've all grown used to in the fast-aging world of AM/FM radio.