my 20 ft boat has 300hp. it is stern heavy, and 55hp "over powered". its declared as 300hp with my insurance company so no issues there. IMO its a perfect amount of hp for the boat, jumps up on a plane, with 2 or 8 people, doesnt care about being loaded up, cruises at 2.9mpg at 3200rpm and best top speed was 52mph. it does what i want. low rpm cruise and jumps when i punch it take the boat for a sea trial, if you like the way it performs go for it!