Hoka has made a splash since it was introduced nearly a decade ago, it just looked different. The first of its racing shoes, the Carbon X pushed the envelope in spite of Nike’s earlier introduction of a tall stack racing shoe with a carbon fiber plate, the Zoom Vaporfly 4%. The Carbon X2 takes the orginal Carbon X and pushed its technical development to the next level. The upper is a stretch mesh, with differing weave in the medial and lateral sides of the upper – a little more supportive medially and a little more breathable laterally, all put together in a monosock knit. The fit is a little better for the “normal” foot i.e. more of the medium arch height medium width, but regardless, try them on to see if it fits. The midsole is ProFly X foam which delivers a bounce, enhanced by the curved midsole plate to roll you to the finish line. The carbon plate is visible through the midsole, as in version one, and its stiffness requires the same adjustment as the original versions of their racers (as with all of the plated shoes – regardless of the brand). The outersole is durable and adds a little extra layer of cushioning in the mix. If a marathon PR is your goal, the Carbon X2 is designed for that kind of performance.