Very negative: the first unit is a channel was broken, returned. A basic system error is that the transport bag, the rubber feet located on the device at the on and off slide of the pouch may be torn off. I have so damaged the unit for the first use in mobile applications and demolished the rubber feet. I have to say that something does not go. The device has not been tested enough for mobile use. Then the volume knob had broken with me and has dropped. Denon makes for many years good equipment and has a lot of experience, there's something even amateurish bad !! The level of electrostatic headphones is just adequate. Positives: The sound is good, appropriate accessories and, where the I-Pod compatibility. Denon must urgently eliminate the weaknesses, then you could possibly issue a buy recommendation. At the moment the device is not fully developed. Too Bad !!!