The Kestrel BOA fits this profile, ditching matching-kit XC looks in favor of light, performance-oriented designs with stiff soles and Five Ten's trademark Stealth rubber for exceptional grip and performance.
Five Ten also upgraded its lugs and midsole, providing more support when pedaling out of the saddle.
I found it to be comfortable on long rides; its abrasion-resistant uppers held up well when repeated contact occurred with rocks; while its Boa closure system provided on-the-fly adjustment that wasn't easily undone like laces would.