So we decided to replace our 13 year old pontoon powered by a 150 Yamadog (which has been a great engine even if slow on a 24' pontoon) with a 25 footer with 300 V8. I never knew I could like a 4 stroke this much. It's really smooth and torquey. I would have loved to have waited for a 450 but the price tag leaves me chilly and would have to go to 27' to get the rating which makes the price even worse and the bigger boat won't go in our boathouse. Seems odd that all of the dealers around here seem to be rigging these with the Merc 3 blade Evolutions, but it doesn't have any tendency to fan in a sharp turn. It's got a 17 on it and turns about 6200 at 45 MPH or a little more, so assuming 1.85 gears it's slipping upper teens although I'm not feeling it. I'm thinkin' about trying a 19 on it but the dealer thinks I should leave it alone. Pluggin' that into the prop calculator it looks like it oughta' drop the RPM down to about 5600 if it doesn't increase the speed which I would guess it would slightly. I'm just not sure how these newer engines with all their smarts start adjusting themselves to more load but I don't like the idea of turning it past the factory recommended redline o 6000 frequently and I doubt we'll be pulling anything with it.