I have XM and HD.
Pretty much, what it comes down to is:
1) Channel choices - Right now, no matter how close you are to a major market where everybody (or, almost everybody) is broadcasting in HD and (most are) carrying multiple streams of audio, satellite radio still wins. Here's the eventual ideal thing for HD radio - When you're in the car, and you're near a major or medium radio market, you can probably get around 20 FM stations... If each of them broadcasts 3 channels of audio, then you've got 60 stations to choose from. That's pretty good. That could be a deciding factor for people who don't want to pay a monthly fee for radio.
2) Cost - Whether or not you want to pay for radio. Some people are STAUNCHLY against paying for radio. Once you can get 60 HD radio channels in any given area, those people will gladly go with HD over satellite. I think most of us who are satellite radio subscribers will agree that $13 a month is a decent price to pay for not having to stumble across commercials on your favorite music channels. (Yes, a couple of XM music channels that are programmed by Clear Channel have commercials, but XM also has non-commercial near-duplicates of those channels.)
3) If you have very narrow musical interests, and typically only listen to one or two stations, and you absolutely can't stand commercials, HD is not for you. HD-1 channels are simulcasts of the main stations that you get on a regular radio, so expect commercials on those right now. At this time, most HD-2 and HD-3 channels ARE commercial-free, but that will eventually end as broadcasters have to start paying for the equipment necessary to broadcast those channels (as well as make a profit!)
I love the concept of HD radio, but right now, as far as channel choices go, it just can't compete with satellite. I think radio is pushing HD way before it's ready for primetime. They should've stayed away from spending the money and spot inventory promoting the hell out of it until you can get at least 50-60 channels of programming ANYWHERE and EVERYWHERE you drive.
Here's my vision for HD radio: Suppose you're a jazz music fan. You're driving through an area where you're listening to WXXX-HD2's jazz channel. (If they want to save some money, they could even have the programming come off of a network, instead of being programmed locally.) As you drive out of WXXX's coverage area, you drive into WYYY's coverage area. They should make an HD radio receiver where, as the WXXX signal gets weak, it automatically and seamlessly switches you over to WYYY's HD2 channel that's running the same jazz format.
I don't know if the technology will ever get that far, or...... Will Wi-Fi-equipped car radios finally see the light of day, and trump everybody? A wireless broadband connection to your car radio and over a million channel choices! (That won't cause TOO many accidents
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