I wanted better torque, better hole shot, and lower planning speed as well with my I-4 Yamaha 200s on my 2501. I flipped out the factory Yamaha three blades for Solas SS 4 blades. Wow! What a difference. Yes I lost about three mph off the top end but my engines are so much better now in so many ways. Cruise speed is effortless, hole shot is incredible. Plus, with my four blades I actually get up to around 5900 RPM at full throttle. My three blades I can only get up to about 53 to 5400. prob slightly overpropped from the factory. (?fuel Econ?). My bow barely moves when I give it full throttle now and no trim tabs to get on plane. It’s fantastic. I can have a heavy load and cruise in without any issues keeping speed or keeping on plane. In short it’s made it a different boat. I won’t ever go back to three blades with my set up.