I have the DS415m and think they are good servos. I overhauled my EXI 450 to a torque tube. Then found a 450pro DFC kit for $120 no electronics. Had a 3Gx laying around from my IKon upgrade. One of my best upgrades. If I factor in all the actual 450 parts over the past 3 1/2 years the helicopter cost me $2,500. Haha
Ken