I've heard of it, but never seen one. Don't know anything about it, though.
Well it uses a standard file formats so that's a start.
One thing it lacks over other players is accessories support. You won't get all the fancy stuff you'll see compatible with Zune or Ipod. Plus the drive space is pretty small. That wouldn't matter much for music or pictures, but it'll matter for video.
I have a feeling it probably doesn't have a pretty software interface, either. Getting files onto it might be completely manual (though I can't really say for sure).
If those things don't bother, it's probably a good device. The price is certainly hard to argue with.