The other option is the more portable DVR Travel Adapter Kit (£42), which includes a 102mm (4-inch) adaptor that snaps onto the 504's dock connector. It's easy to use and transport, but it lacks the depth of ports on the dock. Recording 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.
What you do get in the package is pretty weak -- a proprietary USB cable, earbud headphones, a 504 dock module (for use with the DVR Station) and a sad excuse for a case. Just the basics -- you don't even get a power adaptor as you are expected to power via USB. If you want AC power, you'll need to spring for the £27 Docking Adapter Kit, which includes an adaptor that allows you to transfer photos to the 504 from digital cameras.
Sound quality is decent at higher volumes (bright highs, average low end, punchy mids). It seems that Archos has fixed an audio playback flaw (hissy, crackly sound at low volumes) found in early 604s. Archos even added gapless playback of music files (before Apple).
Widescreen AVI movies (at 720x480 pixels) looked amazing -- movies certainly can be watchable at this size. Video piped out to a TV looks good (depending on your original file), though the presence of compression artefacts leads us to believe that the docking station with its fancy outputs might be overkill. We do love seeing the crisp Archos interface on our televisions.
Processor speed is responsive -- especially scanning through video, though there are some light pauses in the menu. Photos and videos load quickly. Battery life is impressive with the rated 17 hours for audio and 5.5 hours for video -- we'll update with our official battery-life results when they come in. The removable battery makes a huge difference. Unlike in the 604, the 504's battery takes up the entire backside. When the battery is removed, you get clear access to the Hitachi 2.5-inch drive inside.
Overall, the 504 is an awesome portable for those who don't mind lugging around a gadget that's just a fraction too big and heavy to replace an MP3 player. In return for the bulk (and lack of a kickstand), the 504 offers big drive sizes, better rated battery life than the similar 604 series and the same awesome AV performance we've now come to expect from Archos.
Additional editing by Kate Macefield