I thought they were OK, nice and light, beautifully finished. Functionally good but the ring drive can be a bit draggy, resulting in a slack chain when freewheeling.
This occurred to an alarming degree on my road wheels, to the point of being dangerous on alpine descents. Sold those on!
The servicing thing is a right faff though, and the tools are stupid money.
Now using Royce Ti on the MTB. These are superb, functionally spot on. And you can lube the free hub through the rear axle. Possible downside is they are only available in q/r.