When we want to ski fast, we trust the Tecnica Mach1 MV 130 Boot to keep our foot locked in place, our edges digging into the snow, and our feet warm and functional. The super-stiff 130 flex is about as stiff of a boot as we can find on the market, while the "MV" stands for "mid-volume," which designates the 100mm last that combines a comfortable fit with minimal energy loss.