Been playing with prop sizes, the stock prop 15.5x15 aluminum was ok but seemed the engine was working hard and not performing to my expectations, I know it's a heavy boat but after installing a stainless 15x17 viper prop it seems to like it. Cruises at 28mph at 4200 rpm, quick take off, and top speed just over 36mph. So yes, very happy with it. 🙂 End results, picked up 3mph and probably burning less fuel. This is with 3 adults and 75qt cooler of ice.