A waterproof membrane and 400 grams of insulation kept the cold out in single-digit temps in the mountains above Lake Tahoe, and the tallest uppers in this test (tied with the Pow Pows) kept foot-deep snow out during off-trail slogs (no gaiters needed).
The fleece-lined upper adds a touch of softness to the interior, and the reflective heat-shield in the footbed kept the cold from penetrating the bottom of the boot (we stayed warm down to 5°F). Fit tip: They run small; go up a half size, especially if you favor thick socks.
One tester carried a 45-pound pack on a 15-mile hike through ankle-deep Sierra snow, and concluded the Durand is plenty stiff for winter loads. The support comes from a polyurethane midsole and TPU shank. The high ankle is reinforced with a double-layer of suede, which gave excellent support for those with vulnerable ankles.