Subscription radio is not something that's taken off over here in the UK, but if you're in the US then there's plenty of choice if you don't like free-to-air FM or tire easily of what's on your PMP. The Gadgeteer's Rob Tillotson has been trying out a chunky little XM receiver made by Pioneer, the inno, and has found that if you're looking for a compromise between rocking your own tunes and sampling a bit of the mobile XM life then the portable device might be for you.
Aside from XM - reception of which is reasonable in areas of semi-decent strength - there's 1GB of internal memory that can be used to store your own music. Alternatively, you can record from XM straight to this storage, although DRM means you're unable to copy those recordings onto your PC. Battery life looks, to my uneducated eyes, disappointing, with the inno managing just 4-5hrs of live satellite radio reception before dying. Still, the generous bundle comes with a full home docking kit (complete with a remote that's as big as the radio itself) so it's easy to recharge.
XM's repeater technology means that even if you're not in plain satellite view you still might catch a signal, although some commenters - while singing the praises of the inno - complain of poor reception in so-called "urban canyons" when driving to work. Other annoyances include the lack of Mac support and proprietary power connection (despite there also being a miniUSB port on the device).
Make sure to check out Rob's review for full details.
Pioneer inno Portable XM Radio[The Gadgeteer]