Whether the curve is dipped or not is up to the DJ software you use, not the controller. The curve control on the VCI only changes the curve of the MIDI control sent out. And Traktor has no dipped curve option, so you either need to use the EQs and filters to balance out the mix, or mix with the up faders.
Vestax track record speaks for its self. This thing is just made so well. If traktor and a pair of turn tables had a baby this would be it. The touch sensor are sick and highly sensitive(you can ajust if to your liking). Another sick feature is the knob on the back that lets you change the crossfaders effect without having to do anything in the software. This thing is a big name in the controllerism field because it very easy to mod. Don’t take my word for it. Go to vestax website and watch some pro’s take it for a spin.