I have an Evo .46 on my Twist. About the same weight as an OS .46 AX. It is mounted all the way forward on the mount. I still had to add about 4 oz or so underneath the fuel tank. The Twist builds tail heavy. A nice thing though is they give you about an inch in the CG area to play with. If you wanna do 3D with the plane, make it tail heavy.

dave...