Oh snap...
Point Jens!
Personally, C4 destroys all other rubbers (both 5.10's Mystique and Onyxx, and Sportiva's various vibrams)...that is my opinion only. I've used it so much i know exactly what to expect and my confidence is high... Predictability if you will...Your mileage may vary.
Jens is a sportiva guy so he probably is doing the same thing as me...he likes what he knows...