May seem a little strange, but the guy that does the prop work for my GN props also does makes props for this guys RC boat, among a few others.
I would have never thought what worked for an RC would transfer to a full size boat, but I guess it does. I learned to stop disagreeing with the guys years ago.
We owe more of our success in GNs to the prop work than we openly admit to. If the prop is right, all the HP and driving can't fix it.