The DYS blue series speed controllers have been setup and developed specifically for multirotor use, no programming required. Unlike generic helicopter / aeroplane ESCs, the DYS speed controllers come preloaded with multirotor specific firmware preinstalled. Best still, it's not just any old firmware; it's the highly praised SimonK firmware, which is optimised for multirotor applications. It's designed to improve throttle precision but most importantly it can radically improve flight stability. It works by increasing the ESC refresh rate, in simple terms this means a SimonK ESC tells the motor what to do much more frequently than a non-SimonK ESC.