[SimonD]

Just to add something here.

I have owned both the AV420 and the iRiver PMP's (120 and 140). I owned the AV420 first and because of my experiences with it I moved onto the PMP.

When I first got the AV420 I loved it, the look and feel of the device is all there, it looks professional and feels solid in the hand, all round I was really pleased with it. When I turned it on I loved the UI of it, again it was really simple to use and I was pleased with it. Because I am a tinkerer I upgraded the firmware on it to the latest versions and carried on using it for a while. Now I wasn't using this device for music, infact its only recently that I got myself a large capacity MP3 player (Lounge Grey H10) and I only ripped my cd's when I got that. My reason for the AV420 was purely watching video content on the move. I travelled a lot on the train, sometimes for hours at a time and rather than taking a book with me I liked the option of watching my favourite tv programs (don't get me wrong I love reading but there are times when light hearted tv works better than a book).

I didn't use the AV for ripping off the tv, I actually got my rips from the 'shudder' net.
These were all preripped divx files that I reencoded using V-Dub or DrDivx or PDE (during that time I learn alot about encoding) and for a time I was happy with the AV (I was using the Divx5.11 codec) Unfortunately something happened that caused all of my encoded programs to lose sync. I did a lot of testing and worked out that it was likely due to an incompatibility with the firmware and the codec, Archos don't actually licence the Codec engine from Divx so it's likely that when Divx updated their codec to 5.2 they changed something that the Archos couldn't work with.

Needless to say I now had a device that gave me content that had slight syncing issues, now these issues started getting to me, so much that I bookended the Archos and purchased the PMP.

The PMP was great, it played all of the content perfectly and I was happy, infact I was so happy with the PMP that when I smashed up my PMP140 I purchased a new PMP120 for spare parts. Unfortunately though, iRiver then upgraded their Encoder to only work with the 5.2 codec, in my defence I didn't actually use the encoder but I had it installed on my PC, at the time I had only been using the 5.11 encoding codec but when I installed the update it over wrote it and upgraded it to 5.2. It now meant that all new content had that slight sync creep into it.

Since that time I haven't really used the PMP too much, not because of that issue as such (I had preencoded content that still works a treat on it) but because I am away in India and using my laptop to watch content instead.

One bit of advice, out of the two I would really use the PMP over the AV4, I am not too sure how I feel on the PMA either.