You can manage it all on a Windows PC with XM/Napster software for downloading music and moving it to the Helix, but there aren't versions of Macs and Linux PCs. The service's 1.5 million songs is second rate, and ripped CDs come through at a maximum data rate of 128Kbps--hardly high fidelity. The Napster interface is similar to iTunes, with the ability to drag and drop songs, move them between the PC and the Helix, and burn CDs, although not with any XM recorded content. Unfortunately, the Napster software takes forever to notice that a new CD is in the drive and sometimes requires a restart.
The Samsung Helix YX-M1 comes with all you'll need for home and personal use, with earbuds, a tiny remote control, a desk dock, an antenna, an AC adapter, a USB cable, a holster, and cables, but it lacks a car kit, which Samsung sells for $70. While the Helix was sensitive enough to grab signals that the MyFi couldn't pick up, it ran for nearly 10 hours of digital playback, but only half that for listening to XM radio--far short of Samsung's 16-hour claim, although similar to our experience with the Inno. Happily, it charges in between 1 and 2 hours, and the battery is removable, so you can always purchase an extra.
The Samsung Helix YX-M1 feels good in the hand but gets warm after a few minutes of use, and unfortunately, it doesn't work with Altec Lansing's XM3020 speaker set but will work with a new drop-in speaker that's coming out in June. As far as filling it with music, it took a tedious 2 minutes, 50 seconds to load it with 10 tracks that add up to 48.3MB. The Napster interface counts off the transfer but oddly starts at 50 percent, and if you run out of space on the Helix, the software just stops, with no indication that something's wrong.
In addition to a user guide in English and Spanish, the Samsung Helix YX-M1 comes with a quickie setup sheet and a list of XM programming channels, but the guide misses the fact that you'll need to restart the Helix after upgrading its firmware. Samsung guarantees the entire unit for a year, which is better than Pioneer's 90-day warranty on the Inno battery.