I have the AV604 (30GB disk) and the AV605 (4GB no disk SD card slot). The mini-docking station/charger has a USB host port (like a PC) which allows you to plug in either the camera directly or an external card reader.
The ARCHOS certainly works at USB2 speeds but on both of mine I've found that the download via USB Host is pretty slow - something like 1MB/sec. I do it at the end of the day back at the hotel while I have dinner.
Charles
Nikon D800, D7200, Sony RX100m3
Not buying any more gear this year. I hope