These mounts are junk. On my Hanger 9 40 Ultra Stick the mount failed from metal fatigue after about 200 flights. I have never had a prop strike. These mounts don't stand up to high vibration. The vibration I am referring to is not from a unbalanced prop either. I run a APC 11x5 on a TT 46 Pro. The crystalline nature of the cast aluminum alloy can be clearly seen in the fracture. The mount failed just after a take-off after a touch and go. Fortunately, the engine hung up on the throttle push rod and I was able to dead-stick safely with no additional damage.

I guess the reason most people don't seem to have a problem is either that they don't fly that much or that they don't run at high RPM much.

Safe Flying!