Those Knipex and NWS are essentially the same compound leverage design for less hand effort. I have the exact NWS Fantastico 8" cutters you mention and love the looks of the tool especially the red and gray multi-component grips. However, the cutting edges don't perfectly line up so when they come together and I continue squeezing they slide past one another 1mm if I squeeze tightly. The first thing I cut with the NWS 8" Fantastico Cutters is snip 1/2" off a black all purpose screw. Since the cutters are rated for 3.0mm piano wire I thought this would be fine. Well it cut the screw with much effort and left damage to the cutters so now you can see through the cutters when closed. Now I know I should have used a different tool, like a Knipex CoBolt Cutter.
NWS pliers are nice and I have a whole set of them since they look awesome, are made in Germany, and are less expensive than Knipex. My experience with both brands is NWS are good, and Knipex are great.