Orignial Madness made by ZN Line, great bird.

Designed for the YS45 or a YS 63.

Flew mine on a YS45. It hovered it and had power to pull out, however it was lacking in power. I put a OS 50 on it later in life and it performed better.

Go with the 70 and a 13-4W APC and see how it does. Not sure you would be happy with the 46 even with the pipe.

If you are unhappy with the knife edge and/or the roll rate, remove the wing tips.