Ive got a Creative Zen: Vision M and it plays audio (duno bt lasts ages lol) and video (4-5hrs).
It supports many different video formats and if it doesnt you can just use the program called iriverter and it will convert it exactly to the the format, res and bitrate needed. I use it all the time to direct rip from DVDs it a good little software.
You can get it in 30gb and 60gb.
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