The mixer has crisp movements with all of the knobs and the lights seem brighter which is a nice steady reminder of what's going on at any point in time

The only downside is you do not have any idea 'where' the wheel is like some other controllers(no display inside the wheel, led lights on the outside, etc) so you will have to keep your eye on your computer screen if you need visual cues for scratching

The differences will stand out most for those who use their S4 often with a lot of Traktor features: new flux mode, matching-color cue lights, brighter / more colorful lights, and a much more solid feel.[Update 12/13