Though it doesn't cover the same ground as the Cowon, the 504 can handle your files, which in part will be transcoded via Windows Media Player, the de facto jukebox for the Archos. Though we'll comment on video performance later, the 504's screen is amazing, and video controls are quite responsive.
Recording video and audio is a breeze, and the results are worth your while. As long as you have the recoding adaptor, you can record (MPEG-4/AVI with maximum 640x480 pixels at 30fps) from a wide variety of sources such as DVD (it's Macrovision compliant, so you can't watch recorded files on any other device), cable and satellite. Audio recording (PCM or ADPCM WAV) is similarly intuitive and effective.
Though the built-in recording scheduler works well enough, and you can download show schedules via My Yahoo, the process is not as smooth as you'd think.
The 504 can also play MP3, WMA, subscription WMA and WAV files. Support for album art, bookmarking (for videos, too), ID3 tag-based browsing (via the ARC Library), gapless music playback and the solid playlist creation highlight the 504's audio features. We were disappointed with the quality of the newly added EQs.
We do like the fact that upon connecting to a computer, the 504 gives you the option of UMS (PC hard drive) or MTP (Windows device) modes. Transferring to and from Mac (drag and drop) and Windows (autosyncing) was clean and quick.
The 504's photo features are neat. One method for browsing is the thumbnail mode, where you get 54 thumbnails that magnify as you pass over them. Slide-show transitions are professional, and you can zoom in multiple steps. We think it's a great photo viewer.
Part of the reason the 40GB 504 comes in at £195 (slightly cheaper than the 30GB 604) is the lack of accessories. 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.