RE: PERFORMANCE ADVANTAGE GWS DRAGONFLY DIRECT DRIVE/VS/GEAR DRIVE?
A direct drive is one where the rotor is attached directly to the motor. The size of the rotor is also smaller and spins faster.
A gear drive is where the rotor is attached to a gear, and the gear is meshed with another gear on the tail motor. The rotor is bigger and spins slower.
A shaft drive has no tail motor, instead it changes the pitch of the tail rotor to control the rudder.