Jon, I am still @ 81,6kts (94mph) with the Hydromotive QIV OT 28p cut but I am now testing the Mazco RE3 30p I bought from Roy R and I have about 650rpm to the limiter.
As Whipper pointed out I may need to adjust the prop shaft height up to the last hole, I will try to bump the trim before I do anything as I run the Mazco with less trim about 4 while with the Hydromotive just over 5.
The reason I wear a helmet is that last year a friend of a friend made an unplanned stop and on the way out of the boat used his face. Broken bones, broken jaw and no teeth on one side.