Destin at Smarter Every Day did a video about these motors a while back that was really good: https://www.youtube.com/watch?v=VPSm9gJkPxU

The guy he interviewed in that video, Prashant Singh, is credited in one of the pictures in the article.

This is fun to watch too

https://youtu.be/Asp2Sg-AN-g

https://youtu.be/v3jI43YJQMg