Thankyou for Jack . your post is help a lot guys here or some flying site they have same worry about a optional parts or eqiupment bad quality or not strong enough make their lovely models be accident or crash . So i have same thinking about the risk , so i make decision to make a bigger size . the gear is same trex 700 . i think is no problem in the strength , they are very hard 3-D . so it should be very big confident i use the bevel gear . i think no need warning guy don't over 6s !!! He ! He! ok start the bigger version tomorrow , it will come out about two week within .