I'm still glad I went with a 4 stroke and not choking fumes on the downwind troll..but depending on how much you use your boat, your fuel savings could be offset... as remember 4 strokes need an oil and filter change each season. That's $150 +labour on my Verado it takes 7 litres of oil that's $49.99 / 3.78 litre jug, an oil filter and a quart of lower end unit fluid. A 40 HP isn't gonna cost that much...but it's still a litre or two of oil and a filter. My 25 Honda costs me about $90 to have the oil/filter/lower unit/winterize each fall when I leave it for the marina to store away...compared to a 2 stroke that would need nothing but the $12 or so of lower end unit oil and a quick fog of the cylinders.