I hit them side by side and thought that the Kai'li had a better ball flight and feel. The Kai'li was a 60x and the X was a 60s. Also shafted with different heads so that had something to do with the outcome I guess. The other guys who hit both on the same day thought differently though, as Dale says it's all subjective. So I guess my advice is that you should try both(X and Matrix) in the Yammie and hopefully you'll like 1 of them!