That is the best way, to phone mermaid. If the boat is a fast one, it does not mean that it has been uprated by mermaid though. Just by tweaking the fuel screw can uprate the power at WOT quite a bit. Very few P22s have actually been uprated properly above 165 hp due to the costs involved.
Also factors such as weight, fuel onboard, clean hull, good prop etc can make a massive difference. I always have more fun leaving my friends at the dock, making the boat lighter, and taking it out for a spin on my own. - mmm I wonder why i dont have many friends!