XM Satellite Radio was launched in 2002 and has 2 million subscribers, most paying $9.95 a month for just over 100 digital quality radio stations streamed and available from coast-to-coast. XM's 68 music channels are commercial free while its other in-house and syndicated offerings may contain spot ads.
XM sent out its first two satellites into space -- appropriately named Rock and Roll -- but has since set up a third satellite to ensure continuous operation as the originals wear down.
On the plus side, XM is three bucks cheaper a month than Sirius. That does add up over time. However, Sirius has also paid up for exclusive NFL and NHL broadcasting rights. So if you are drawn to satellite radio for live sports because coverage of your local team's games isn't enough, Sirius may be worth the extra money. That doesn't mean that XM is without its sports programming. It does come with Fox Sports. However, the games themselves will be on Sirius (or, perhaps, on your local radio station dial).
Sound and Vision magazine took both Sirius and XM for a test drive and rated XM as having superior sound quality. But don't get too hung up on that because they both sounds awesome, way better than what you're used to listening to on the AM and FM bands.
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