We got excited about K2 SpYne 130 ($650) when we first heard about them last November.  Built for hard-charging skiers, this all-mountain boot uses a rivet-free “energy interlock” that locks the cuff and outer shell, fore and aft, letting it stretch and build up power for a smoother, more efficient load transfer. The “powerfuse spyne” is a Y-shaped configuration that runs down the rear of the boot, strengthening it and significantly reducing chatter and excessive vibrations. Four buckles and a wide upper strap lets you dial in a snug fit, and a bevy of other details—dual-cuff alignment, padded mid-grip, replaceable outsoles, alloy buckles—round out the boot’s features. Considering this boot (and others in the line) is the product of more than two and a half years of research and designed—and are the first boots that K2 has ever released—we have some faith this boot is going to be a contender. —Nathan Borchelt