As with the Clip+, the CIip Zip is an excellent MP3 player.. that is very, very slightly bigger with a bigger colored screen.
I've not had any of the problems as described by others, but then again I don't run the stock Zip firmware much either. But, I've read that the Zip (like the Clip+) can crash when it encounters unexpected file types or corrupted files. Also, Welshnick is right about the sound on the European set-up.. the EU is trying to protect our ears apparently. Too late for some of us EU!!
I suspect that I'm not allowed to post URLs. So, I'll just say: Rockbox, for free and better firmware. :)