My wife got XM for her car, then two weeks later I wanted one. Have two now.
Love 'em.
'There's always something on regular radio.' That's true. In my case, it's always crap. We theoretically get about 30 channels, AM and FM. 10 of them are religious music or talk. 6 are 'rock', three of which are new rock, which I hate, and one is 'soft rock' which puts me to sleep. One is college, which is good some of the time. 8 or 10 are country, which I don't mind, but not that much. And about 6 are 'urban', ie, hiphop which I can't stand. Not to mention up to 22 minutes of commercials an hour.
XM offers 68 commercial free music channels; I have heard precisely three songs on XM that I *ever* heard on the radio. I have heard I believe 3 repeats on XM, and that was over a three week period.
If you like 'popular', which is generally 'whatever Clear Channel decides to play', yes, you will be disappointed in XM. I like a little variety with my music. The radio stations around me will *never* play Dead Kennedys, Anti-Heros, The Damned, PiL, Foetus, etc. And that's just off one channel 'Fungus.' Heck, I even enjoy listening to 'Audio Visions' [sort of the Enya/Tangerine Dream 'new age' stuff. Very relaxing, which helps to counter the punk on Fungus.]
Go here to see what's playing on XM right now:
http://xmfan.com/guide.php
Hit that a few times throughout the day, and see if it's stuff you would like to listen to. I enjoy listening to stuff I'm not familiar with and discovering new bands/sounds. I've even enjoyed the clean/notclean comedy channels recently, playing anything from old Laugh-In skits to Bill Cosby, Jeff Foxworthy, Dennis Miller, Guido Sarducci, etc. Right now Laugh is playing a Woody Allen piece.
Free radio is good at least pricewise, but at least in my market, unless I like 'New Alternative' or 'Hip Hop' or 'Country', I'm out of luck. Sometimes things are worth paying for--satellite radio, IMHO, is one of those things.
The ten bucks a month--how many CD's do you buy a month? That's less than one cd, and offers you exposure to millions of songs, plus special programming. [They did an all-Ramones day a while back, and on D-Day, they played ~36 hours or so of D-day broadcasting straight from the history books.]
You can go here
http://xmorsirius.com/ for some info and comparatives on the two providers.
XM offered a wider playlist and was cheaper in hardware and monthly cost than XM. Both provider's websites will let you sample their wares.
Do you travel? You can travel the country and still listen to the same 'channel' with the same type of programming, rather than having to tune into 'East Podunk's Farm Report' or 'Brother Jim's Traveling Salvation Show' [No offense intended to anyone who listens to those, just saying choice is good.]
XM beats the crap off of 'regular' radio, at least in my market [Raleigh NC] and based on my tastes.