I own a os 1.60 fx and a saito 1.80 and i will tell you that the four stroke is in absolutley no way more economical than a 2 stroke, it uses twice if not more fuel than the os. my 1.60 fx is swinging an apc 18x8 at 8900 rpms and the saito 1.80 is swinging a 17x8 at 7700 rpms.I personally ( and only my opinion ) will never buy a large 4 stroke again, i think they are a pain, not any more quiet ( my 1.60 with a bisson muffler is quieter than the saito ) and waaaaay more finicky. just my opinion.