Having used kangaroo Lakes, Bontragers, 15 index stiffness top of the line, I was expecting a semi comfi performer, especially considering its synthetic materials. However, these shoes are surreal. First, that varus adjustment of 1.8 degrees eliminated wedges. Then the ergonomics- NO PRESSURE POINTS! Yes, I could have gone wider, but it would have been a tad too roomy. By keeping the front LOW med tension, and top MED, the forefoot has more room that any single Boa system I ever used. Then the speed- paired with Speedplay Aero, the want to revv revv revv 90-105 RPM. I was not surprised to see 1-2km hr gains over 35 km hr, and steady pushes to 40. Ironically, I was semi recovered from a flexor fascia injury, yet I was healing while galloping through 40, 50 60 km sessions. No stiffness issues, despite high effort and out of winter 86kg, got ways to drop to 78... Easy to lean in and adjust; best adjustment is 5mm behind metatarsal line (feels nearly aligned from the seat). They do work terrific with the Specialized body geometry soles. Initially, they almost numbed my right foot, but front BOA tension resolved it. They are tru to fit so if you measure 270- you are a 42.5- not 43. Stiff, forgettable, fast, some 300 grams each with cleats, they are a sort of techno vodoo from Specialized. YES, Lake kangaroo is more comfy on the top, but flexier and SLOWER. Bontrager loosens. These things are LOCKED AND LOADED once set, and good to go, with only tightening needed if deciding to push above 40 km hr. Comfy uphill, caught myself getting out more often. Again, I cannot fully explain how Specialized delivered a shoe improving my speed by 1-2 km/hr, fast, light and forgettable, they just did. ONE DRAWBACK- they are techno age ventilated and they are AS COOL AS THEY LOOK COOL. 2021 Spring came in March- Canadian record. Below 15C (59F), foot gets chill in racing socks. Below 10C (50F), feet get COLD and 7C (45F) numbing cold, and no room for wool socks (perfect fit after all).