I have a Rio Karma and would recommend that you look at one along with the other two you mentioned. The price is in between the ones you mention. It has a few features that the other two do not. It has an easier interface to use, has cross-fading so there is no pause between songs, comes with a docking station that can connect via USB, ethernet and has RCA line-outs, plus it is smaller than the other two by quite a bit.
Another benefit is that you can use Ogg Vorbis and FLAC format compression instead of mp3 if you want.
