1. The Gore-Tex XCRlined Sandstone has a strip of airy mesh along the tongue (where it can best release the foot's heat) and leather/tightly woven mesh along the sides, where durability is key. The upshot: No sweaty feet or blisterseven after four back-to-back 12-mile daysand no blowouts.
2. Adjacent lugs are positioned at opposing angles. When the shoe strikes the ground, the lugs deform slightly, absorbing energy throughout the heel-to-toe motion. Sportiva calls it the "impact brake system." We call it regenerative braking for humansour legs felt better than expected at day's end.
3. That spring in your step? It's actually an arc of TPU plastic that runs along the sides of the shoe. In addition to transferring energy from heel to toe, it prevents your foot from rolling on rocky terrain. Compared with other reinforcement materials, molded TPU is less clunky; it doesn't stiffen your stride.
4. A typical toe bumper made of thick rubber can make a shoe feel cumbersome. So La Sportiva sprayed a lightweight mixture of sand, glue, and rubber directly onto the Sandstone's toe box. The stuff saves weight, and its low profile and tacky grip afford an approach-shoe feel when you're scrambling.
5. The Sandstone ages better than Mick Jagger. After weeks of abuse, the rubber-reinforced midsole was as springy as on day one, while the rock-solid upper showed only the slightest (and most superficial) signs of wear. Or as one tester more bluntly put it, "It's a tough bastard of a shoe."