Awesome, just awesome! I can't believe I waited so long to switch. I believe it is lighter than the XTR cassette I had, looks pretty slick, shifts amazing and seems to stay clean a lot better as well.
The price can be a bit steep but considering it is made out of tool steel apparently it is supposed to last 4 times longer than an aluminum cassette, time will tell but so far I am hopeful.
The back end of the bike seems lighter as well, not sure the weight loss between the Hub Driver and the cassette but I feel I can pop the rear wheel up much easier than before (not that it took much effort).
If I had a 2nd bike, I'd be putting this on it as well!