Dave, that's like asking who makes the best vehicles, Ford or GM. You'll get no definitive answer.

Saito's are good engines and so are OS. If you also consider a Magnum 4-stroke, then you're adding Chrysler to the Ford vs. GM mix. I have Saito, OS and Magnum 4-strokes. Even compared to my new OS 1.20 4-stroke with pump, I think the little magnum .80 4-stroke runs smoother at all RPMS. I believe the OS 1.20 4-stroke has more "grunt" than a comparable Saito.

At the end of the day, I believe they're all very good quality engines that, if properly cared for, will last many years.

By the way, that Magnum .80 4-stroke is on a .40 size warbird, and it is a real performer.

Mike