For those torn between the 604 and the 404, most people will probably be won over by the nicer screen and removable battery of the 604. The 604 is slightly thicker and 25mm wider but offers so much more. But ultimately, you can't deny the 404's more pocketable and manageable size.
In order to record audio or video, you need to purchase one of two optional kits. The first is the Archos DVR Station, a dock designed to fit in with your entertainment system. This £62 kit (with a nice remote control) can record virtually any video source, including cable TV, DVD player, camcorder and so on, as well as line-in audio. It features virtually every input and output you'd care for, including S-Video in and out, component out, standard USB and even S/PDIF out.
The other option is the more portable DVR Travel Adapter Kit (£44), which includes a 101mm (4-inch) adaptor that snaps on to the 404's dock connector. It's easy to use and transport, but it lacks the depth of ports on the dock. The AV500 actually shipped with a docking pod, making it record ready out of the box. So you're actually paying a little less (with a smaller screen of course) if you add the recording hardware -- not a bad move by Archos, since you can save some cash if you don't want to record. Recording, however, is one of the prime features of this 'DVR', and our advice is to get one of the two kits when you buy the main unit.
If you want to use the 404 as a USB host and you own an AC adaptor (the 404 ships with only a proprietary USB cable), you'll have to stump up for the Docking Adapter Kit (£27).
The 404's revamped photo features do deserve a mention. One method for browsing is the thumbnail mode, where you get 64 thumbnails, which magnify as you pass over them. Slide-show transitions are professional and you can zoom in multiple steps. Like the 604, the 404 is a great photo viewer.
Battery life is rated for 12 hours for audio (subpar) and 4 hours video (good). Archos's latest firmware update supposedly improves audio battery as well as the overall audio quality. We'll verify this claim soon. We had reported that the 604 was noisy at low volumes -- while the 404 definitely sounds better (the 604 has improved as well), there is still the tiniest electrical static. Overall sound quality is very good, though. It's very bright sounding and punchy, which we prefer. The built-in speaker is okay, but not great. We also appreciate the addition of the set of preset and user EQs, but they don't dramatically affect the sound. We have to give props to Archos for adding true gapless playback of audio files.
The unit can pipe video out to a TV via the headphone jack (though you'll need to provide your own cable), and high bit rate video looks very good on a 20-inch screen. Recording video is simple without any headaches (you can record in MPEG-4/ADPCM/AVI at a maximum of 640x480 pixels and 30fps). Scheduling recordings is easy enough, though we'd love a programming system that's more integrated and intelligent (Archos tried this with the PocketDish-branded versions of the AV500) in the same way the Toshiba Gigabeat S can playback Media Center recordings.
Overall, the 404 is an excellent alternative to the current iPod, with its compactness, rich feature set, excellent video performance and, of course, competitive price. The 404 is a PVP in an MP3 player's body. We would recommend spending the extra money for a recording kit, though, as using the 404 as a DVR is what makes this device so attractive.
Additional editing by Kate Macefield