Dont just press the strut piston and look at it rising to check for its performance, the rise is a proof that it is postiviely gas charged (gas is used to prevent foaming the oil inside) when its extending out try pulling it with force, if the piston rod moves easily and eagerly to your upwards force, the strut is not good.
In my experience, kyb is “meh” and not that great, they are not even half as good as OE items the factory put in, so dont have very high expectations.
