Used KMC X10SL for some years now on different cassettes and gearing like 2×9, 1×9, 2×10, 1×10, 2×10 Campagnolo. Working perfect. Seems to have a good life too as I am having a hard time to wear down my Recon alucassette. So for us who like light bikes and then light cassettes that costs to much. Then KMC is helping us more. At work converted to euro we take 450€ for a Campagnolo Super Record cassette, you should care about a chain used with such expensive cassette.
KMC have strengthen their chainpins to hold even better. Saying they get double life time from it now. Also getting better outer plates for even better shifting. Stamped XX on the new X2.0 chains so you know it’s the upgraded and not the old ones.
This is for X11SL, X10SL and X9SL