Ability to change the contour curve of the up faders

It would be very helpful for dj’s that love to scratch with the regular faders instead of the cross fader. even when the prime 4 is connected to serato and i change the up fader contour to sharp, the prime 4 for still lags in cutting off the sound. When i use my numark controller, the up faders cut out very nicely when i sharpen the contour of the up faders with serato. Please help solve this, i would really like to use my up faders in the prime 4 the same as i used to in serato.