I have a 19' sled with a 150 on it. I must say I am rather surprised they are suggesting a 90/60 combo. I would be very disappointed if I had that power setup. As is, I plan on putting a SS impeller on mine to squeeze out a little more. When in wide open water, I wish I had the 200. I would certainly put what ever the max is for the boat on it. You don't want to have to run the motor at or near its max constantly or it isn't going to last very long. Its always nice to have some power in reserve to.