The YS is not too heavy for the front of the plane, and it has GOBS of power. If you run 30/30 you should be able to swing a 15x10 with the 1.10 and the plane will love it. IIRC the YS 1.10 is lighter than the OS 1.20 w/ muffler. I'm sure the Saito will fly the plane well too, but the performance with my YS was nuts.