Daniel,
All of those horse power numbers are pretty much useless. They really tell you nothing about the 3D performance you can expect. I have owned almost all of these engines and had most of them on 3D profiles. Believe me the 46Fx, 55ax, and YS 63 are not in the same class as a Saito 100 when it come to 3D. The 100 will swing a much bigger prop giving you better an much more instant thrust. I found the Saito .72 better than the 46 or 55ax for 3D although the 55ax may have as much top end power. The .82 is better yet. In two strokes, the MVVS .49 or the Webra 50/55 seem to work better for me because of the instant throttle response.