I don't know if this has been brought up before, but I just want to put this out there that having unbalanced props may be one reason why cracks appear and get worse over time, even without crashing.

Tiny prop imbalances are magnified when the aircraft is in operation. And among the different parts of the airframe, the motor mounts seems to be the ones who would have to absorb any side-to-side motion of the motors.

Just saying.

I don't know if this has been brought up before, but I just want to put this out there that having unbalanced props may be one reason why cracks appear and get worse over time, even without crashing.

Tiny prop imbalances are magnified when the aircraft is in operation. And among the different parts of the airframe, the motor mounts seems to be the ones who would have to absorb any side-to-side motion of the motors.

Just saying.