My beef with an all aluminum quad is not the strength but the vibration problems. Aluminum has what I call " sympathetic" vibration qualities. Say you have a out of balance motor. Aluminum will transfer that exact vibration frequency down the arm and into the frame and finally into various components. I don't know the scientific explanation for why this is. It just is. Using wood inserts accomplished 2 things. It added the strength inherent in composite construction and damped vibrations. The internet is full of "fixes" for aluminum vibration issues. They usually involve using rubber damping between the arm and the frame. now you introduce flex. A whole other can of worms. A better alternative is to attach the arms to a frame made from a harmonically "dead" material. Usually woven carbon fiber or thin plastic/foam/plastic sandwich. Aluminum has a lot of great features for use in quads. Motor mounts, bracing, various attachment hardware, heat sinks and etc. Enough! That's my opinion and I'm sticking to it!! LOL