[jhautz]

If they are getting 100mph out of a MM motor on 4s I'm sure they are getting the rpms up past the max rated limit. The motors wont last long that way, and im sure they are pushing them past their rated limits for very short bursts. Not a good idea for general use for sure. They are just taking their chances that the motors can handle it for a short burst. I'm sure that more than a few of them have blown the motors, escs or both by doing it as well.