The following message board helped me decide the exact same decision you're looking at... http://www.pmpmaniac.net/index.php?option=com_smf&Itemid=38
I ended up choosing the AV500 because from the reviews I read, it records picture better, smoother and faster from your TV/DVD than the A2. Also, the video was said to be brighter and sharper. Additionally, you really can use it like a TiVO by setting multiple times to record live TV, where as with the Cowon A2 you can only set 1 time for it to record.
However...the A2 does have other advantages. It seems to have better codec support for some files, though it seems like people have had success watching Divx 4 and 5 files, along with mpeg-4, etc. Also the A2 has an FM radio and recorder, so if that's what you're into, then that might tip the scale towards the A2.
Personally, picture quality and better DVR qualities were what made me choose the AV500 (even though I think the A2 looks much better overall...you must remind yourself you'll be looking at the screen, not the overall player most of the time!)
I've only had the AV500 for a couple of days, but so far no complaints. Good luck with your decision, either way you won't be disappointed!
Can someone please help. I have looked at too many reviews at this point. Does anyone have any insight into these products. I initially fell in love with the look of the AV700 (40gb), but have recently read that the AV500 (30gb) has a smaller, but better quality screen. Then, just to make my decision that much more difficult, someone recommended the Cowon A2 (which I cant find much about). Looking to watch movies and tv programs on the train. (Am about two (2) seasons behind on 24 and need to record season 5 in January) Any input would be much appreciated.

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