Reply to numark ns6 vs Kontrol S4?

I love the NS7, especially the build quality, but its not the best for Traktor. Then I saw the NS6 and I immediately got hyped. The S4 is pretty awesome too, and perfect for traktor, but each has their own advantages and disadvantages, so Im not sure which to buy... I would have to get pretty creative with the NS6 for midi mapping, but I dont believe that would be a problem. Your thoughts guys?