I love my Mando ECS10.
Out of the box, the car is transformed, with a little tuning I got it to be really, really solid!
However 20" wheels + lowering springs = harsh ride on broken pavement. I was playing around with the settings and was curious so I did 0%. all around. It really does help with the harsh pavement, I feel no stability issues at speed. To be honest, it allows the car to squat and it's easier to shift the weight for a little "tail out" action.
Your results may vary, I enjoy mine set at 0%. I do firm it up when I feel like it, but I like it!