So after grousing about the limits of the Sirius S50 device someone turned me on to timetrax, a hw/sw solution that enables recording of Sirius or XM satellite radio. It looks like a reasonable product w/ relatively stable software.
One fear is that the satellite companies, on their own accord or under pressure from RIAA, block this type of product. Another drawback is that the satellite receiver isn't a device that can really be used anywhere but alongside your PC - i.e. no way to take it in the car, to the gym, etc. So i'd really just be recording and dumping to my ipod.
But that might be a fine solution and so I'll spend some time this weekend checking out what the forums have to say about timetrax.