Yes now 2 of them overheat. But which came first? Overheating to demagnetizing? Other then being demagnetized, they have no reason to overheat, and they were not. They ran completely cold. I think they were defective, the motors are tiny and only $6ea. The problem is the shipping cost from China. They have not recovered yet, and it's been days. I read that it's nearly impossible to remagnetize rare earth magnets. They are tiny. 10+ around the bell housing.
It's less than $100 from Hobbyking. Again the problem is the shipping. Took many months for backorder, and $20 per order.