I got to see one of these at an LFS last Sunday. Pretty cool looking and solves the issue of mounting a MH pendant over the tank. I've seen it as low as $220 at Coral Reef Eco Systems (with ~$250 being the norm).
Too bad this option wasn't available last year when I was setting up my 125g tank. At that time all the MH HQI options I looked at were at least $300/pendant (fixture+ballast+bulb). I still may not have opted for it since the four 96w Aqualights I ended up getting were less than $450 total, but it would've been a difficult choice.