Merrell Agility Peak Flex

The Agility Peak Flex excels on the steep, rocky, and muddy trails that one of our editors runs above Boulder every weekend. “My heel stays locked in place when I descend, and it never feels sloppy when I move laterally,” he says, crediting the plastic heel molding and integrated “double-lacing” system for the secure fit. The laces bind the upper to the tongue, providing a snug feel without pinching. Traction and midsole cushion are about average for the category, but the breathable mesh uppers and nimble feel make them a good choice for backpackers who prefer trail runners for summer hiking with a light load. (If that’s you, check fit: Our wide-footed tester says he prefers more space in the toebox for all-day comfort with a pack on.) Tradeoff: Low weight and mesh uppers mean reduced durability.