Here is an idea I think would work but I would love to hear if anyone has tried it already or knows why it wouldn't work. Cheap quadcopters like the Estes have all the electronics of a larger machine, such as the gyros and 4 driver circuits for the motor. What if you built a frame with bigger motors and props and used the Estes as the brain. The motors would be replaced by a circuit that amplifies the power to driver the larger motors. (Estes motors are pretty poor for reliability anyway.) Anyone else thought of this?