Marcel Gm speedos may look tricky at the begining,but when used to them they are pretty easy and when you find the sweet spot to your driving style there isnt much to setup.
These are state of the art escs with tons of options and small increments to fit any driver and track.
I have setuped a few modes on mine to fit my driving style and according to the track and grip conditions I just have to choose the correct mode,obviously I have to know whats been loaded on each mode
That dificult myth are cheap words of users/sellers of much basic controllers.
Actually a Genius120/90 wont win races by its own,but its a great help to the driver
Give them a try and you wont regret.