It proved to be very efficient on my water stones and Shaptons and I'm very satisfied with it. It's fast, no scratches and it does not create hydro lock. Using the entire 9.6 x 4.2 surface allows me to get consistent results on all my stones. I just use it under running water in the sink as it's light and easy to hold. Debris runs into the grooves and right off the plate. I really like this plate at this point.
The lapping plate did a great job flattening my natural and composite stones. Im a sushi chef by trade and have high expectations of the tools i use for my profession. The lapping plate did quite well meeting my expectations of flattening and leaving my stones smooth but not only that, it seemed to do it in half the time as other flatteners i have used in the past.
I have just tested it on my “boys”: 400, 8k and 10k. The deal was done with a couple of passages, and the stones came in excellent condition. In my view, it seems as it has suitable coarseness even for more than 10k.