I just tested it out last night and it didn't perform so well. I ripped an episode of heroes to a 640 X 480 MP4 file which was about 500Mb. Loading it to my iPod 3rd gen nano took about a minute. It took 18 minutes to load the same file to my SanDisk Sansa e250 and after about 40 minutes of waiting for the zune software to load the same file to my 30Gb Zune I just went to bed. It was finished this morning. I don't know how long it took other then to know that it took longer to load the video file then it would have taken to watch.