Hmm... thanks to everyone for all the info. I've heard the complaints about SQ from Sirius/XM, something to do with compression I believe. Too bad in this day and age we can't get outstanding over the air broadcasting.
As far as only wanting classical goes, what I'm mostly interested in is the more obscure stuff I mentioned in my opening post that hardly ever gets broadcast over the air. I already have a huge classical collection and a few decent stations to listen to once in awhile.
But I wouldn't want to reward some satellite radio business with my hard earned money that provides lousy SQ and lackluster service, especially if they may go under in the near future.
It looks like the Sirius/XM jacks on the back of my soon to arrive Sony ES receiver may go unused after all.