I just got my HD990 yesterday, open box, very nice condition, from One Call. comes with one year warranty. Slim styling, almost didn't see the buttons on it, they are not very prominent. somewhat lightweight. All i did was connect the HRS cable to my HK990 and connect the optical output from my Mac Mini to the input on the back. Back panel is somewhat crowded as it also has balanced outputs and coaxial and optical inputs as well as output.
disc mechanism seemed very quiet. either it was the placebo effect or music sounded a little more incisive, deeper soundstage with more midrange inner detail revealed and a little broader soundstage,. Sounds good! heard the same effect with hi rez digital from my mac mini. Nice thing is the display shows the sample rate but not the bit depth.
Very pleased and just hope I don't have the issue with the skipping, good so far.