XM Radio - Anyone Getting It Through DirectTV?

We moved a few months ago into a new and larger home. And long before the move I had my fill of the miserable picture provided by our cable TV service (Comcast). So we set up a DirectTV account and LOVE the service as well as the extra clean picture on every channel. (One of my main beefs with cable was the ghosting on at least two or three of the lowest channels on our cable system.)
A few weeks back we discovered the various XM channels that we get as part of our service package. My main question concerns the quality of the XM signal we are getting vs. that recieved by a dedicated XM satellite receiver. Is there any real difference? I can tell you that the classical channels on XM certainly have a LOT more enjoyable music than much of what our local classical station plays most weekday mornings.
I never bought a separate tuner for XM in the house since I get it on Directv. There is no comparison to real CD quality (redbook) due to compression and transmission quality. It is good enough for quieter listening in my bedroom, but not enough for quality listening. There are issues of compression, transmission to the sat, down from the sat and receiving by the dish. Only part of the equation is the decoding by the receiver. I say, enjoy it for what it is, but I can't see spending the money on a separate receiver unless you want to get the XM channels not available on directv.
I listen occcasionaly to the Direct TV XM stations in both my living room and bedroom. I've got a sperate satillite receiver and stereo system in both places. It makes a big difference if you can run the digital signal through a good outboard DAC. Still, I prefer to listen to the sound from my analog tuner (Magnum Dynalab FT-101 in lvg rm and HK Citation 23 in bed room). I still can't really get used to that compressed digital sound..it's just kind of "thin" and brittle sounding to my ears.
But I'm with you on the programming selection, that is fantastic.
I have been with Directv (D*) for just about 10 years.
A few month back our music stations were swapped out to xm-radio.I probably listen to their music as much as anybody; and then some.
The change from music choice to this xm-radio has been very good with just a few shortcomings. One being the chatter between selections/ or offers to upgrade to more stations. (Different levels of programing allow for more stations.)They just seem to have a play-list on most stations that is much better than Music Choice ever had. One big exception is "Classical Country". Music Choice 829 was more to my liking than all of their country stations combined. However,I can tell you this; the sound quality is only as good as the dac you are using. The sound quality is there !! I doubt their all in one receivers is half as good my 2ch-pmc sound. 10 years ago I had Theta Digital install their coax-out, board, in my Sony box. I use the Audiomeca dac and a 1k dig. cable.So, as you can see digital radio is important to me.
I'm so jazzed!! I just tried my Direct TV I am getting xm radio too. Now , my big question is how do I get digital out to my dac. My standard issue direct tv box has no digital out on the back. Thanks for the great post, I would never have looked otherwise.
I've never done a side by side comparison, but can say that the compression does result in a sub-optimal source. This seems to be consensus in this thread, as well as others. I have found a silver (okay, bronze) lining in this cloud.

In my environment, I run that signal through some pretty respectable digital processing (Meridian 518 for dejitter upconversion, Meridian 565 for processing, out to Meridian digital speakers). Despite all that, the sound just isn't anything to get excited about, but. . .

When I take that DirecTV/XM signal and put it through some soundfield processing, there's what I consider a significant improvement in listenability. I have a more modest Marantz processor in another system, and found the same to be true with that rig.

So, while I'm loathe to 'muck up' a pristine source with soundfield processing, it seems to have a positive effect on lower quality sources.