I have a rio Karma. It might not be on your list, but I like it. It can play OGG and FLAC, and has an ethernet jack on the dock(yes, you can load songs through it). It is also compatible with any operating system that has Java support in a browser. The batteries last for quite a while, mine will last several late nights at the library during finals before I have to recharge it.
There is also
http://www.riovolution.com/