It's an Alpine 700 LCD. I moved stock fosgate unit down, repositioned emergency flasher switch over next to steering column. In the back is also a roof-mounted motorized flip down. Sound is through a digital FM modulator. Sound quality is good and never loses signal. It was the only way to keep factory unit (mainly for steering wheel controls) and still go NAV/DVD.
I have the Kenwood DDX7015 and the Kenwood 3100 NAV in my Audi, and the only thing I like about it more is the ability to control EVERYTHING. With the xterra setup, I have control over NAV and outputs to rear screen, but otherwise, the DVD changer, factory head unit, and XM must be controlled with their own remote. Wish it would all interface through the touch screen, but at least the NAV does...