Is anyone using this head unit?

I like the idea of a dvd/cd/mp3 and navigation all in one.

I wonder how the quality of the audio output is, and it's features and tunability?

It seems to leave a bit to be disired compared to a good cd or dvd player in terms of the tunability side of things. But I can't seem to find an extensive list of specs and features, even from the eclipse website. They seem to focus on it's navigation properties, probably for marketting. Eclipse USA has a bit more info, but is the AU delivery the same spec?

Anyone using it or familiar with it?

has 7 band parametric eq, basic crossover, no time alignment, but very nice sounding head unit not to forget its made in japan

While you are right in saying its tuning functions are limited it is still quite a capable unit and one of the only ones on the market with built-in navigation - which works very well. You do get 2-way crossovers built in and graphic EQ, while it is indeed well built and has a decent GUI (Graphic User Interface) making it simple to use.

has it got optical out??

nope