I am chiming in with the same warning. I did not add any weight and came in with a 5 1/4" CG. I used the recommended high rates as my low rates and the 3D rates as my high rates. I was lucky to get it back on the ground. snapped something fierce. I am a experienced 3D pilot as far as Funflys go. I added weight to the nose (to go to 4 1/2" CG) and backed the low rates way off. When I get several flights under my belt with this bird, I will then experiment with the CG and throws, but not until then. Don't let your pride crash your plane take it slow.