If anyone has any, could you please share your experiences, tips and advice on hooking up a digital audio player to a Linux box (Core 2 specifically)?

I am contemplating buying Rio Karma as it supports OGG and Flac formats but would like to know beforehand if the hook up and file transfer is a big pain in the neck or just a small one.

But if someone has other players that work fine with Linux, then let me know as well. Any advice will be appreciated.