I've seen the Dension "Gateway" products that allow connection of things like USB hard-drives and iPhones to the CD 70 via the AUX connector. The advantage of using the Gateway is that you can control via steering, see track names on the screen etc. I am considering buying one to interface the CD 70 with a USB hard-disk full of MP3s.

The only experience of Dension units I have seen is on youtube or on German forums.

Has anyone here tried a Dension (specifically the Gateway 300)? How did you find it? Did you try the USB interface? Any pit-falls or failures?