Good description:

[https://oscarliang.com/top-5-best-fc-mini-quad/](https://oscarliang.com/top-5-best-fc-mini-quad/)

[https://www.getfpv.com/learn/new-to-fpv/all-about-multirotor-fpv-drone-flight-controller/](https://www.getfpv.com/learn/new-to-fpv/all-about-multirotor-fpv-drone-flight-controller/)