Another small problem that I have had with all of my rotors is the noise. The drive cones and gears spinning around in there dry sure do make a lot of racket. They also make a lot of friction and any energy used not to feed a ball is just a drain on the system.
So like my other rotors I put a lite coat of silicone grease on the gears and any surfaces that touch. this makes things much smoother and quieter. Also from my un scientific test of trying to hold it back while in operation it seams to have a touch more torque. I attribute this to the reduction in friction on the drive system.