Consider the Fastwitch for your next long-distance race. It's one of the few racing flats with stability and just enough volume to tackle high mileage -- even up to marathon distance. Its lightweight features allow runners to effectively tackle speed workouts without sacrificing comfort and support.
The updated materials provide more coverage and comfort - the material has a more uniform, sock-like fit without any noticeable pressure points. The seamless Flexfilm system provides reinforcement to the instep, and securely holds the foot in place. Like the last edition, the materials are still breathable, but simply have a more pleasing on-hand feel.
The stack heights of 18mm in the heel and 14mm in the forefoot provide the right balance of response and just enough cushioning to avoid a sluggish or harsh ride. The forefoot flare helps stabilize the shoe without requiring as dense a medial post. You can feel the structure of the dual density, but it works with the shoe by offering just enough flex to not feel over-corrective.
The outsole layout is similar to the previous version, but doesn't produce the same clunky feel. The updated PWRTRAC pattern covers the midsole from the exposed EVA, which allows this shoe to tackle more miles before breakdown. The two large drainage ports on the bottom provide breathability, cut weight, allow water to flow through, and prevent the occasional stone from catching in the grooves.