I did go with the Quad XS. It definitely has a different feel than Quad 0. Less blade on the ice for sure (especially at the back). More "rockered". Better transitions and maneuverability, bit better agility. Less glide and power off the stride or crossover. I was surprised at how different it feels from Quad 0 given the numbers don't seem too different. I've yet to try Zuperior. Although some other profiles I've had might be similar. I've heard either great things about Zuperior or horrible things. No in between. Prosharp advertises Zuperior is the agility profile, but from what I hear, based on real experiences, it's more for stability and speed. Which makes sense looking at the profile radii. Most people I know think Quads are the agility profiles, not Zuperior.