We've tested plenty of two-pound, 15°F sleeping bags, and we know this to be true: They're either crazy expensive, crazy narrow, or crazy to claim a 15°F rating. Enter this precedent-setting 800-fill down mummy, which is warm, spacious, and affordable. How? It starts with a continuous spiral baffle that drapes insulation around your body more snugly than standard horizontal chambers, while also adding some stretch without the weight and cost of extra seams. Next, the fabric is cut on a diagonal, which enhances flex. The stretch doesn't compare with MontBell's heavier Down Hugger line, which actually has elastic built in, but testers were unanimous: This bag felt roomy to everyone–despite different body shapes–but it never had excess space to heat.
Every other detail is dialed. The hood closes easily around the face, and the zipper runs snag-free despite the wispy 12-denier shell fabric. The DWR-treated microfiber cover proved water resistant enough to keep the down dry in soggy Wales. The fabric breathed well in the humid conditions, and showed no weakness despite the ultra-thin construction. The minimalist design includes no frills–like stash pockets–but testers slept too soundly to complain. The bag packs down to minus-football size, and comes in short (5'6"), regular (5'10"), and long (6'4"). $299; 2 lbs. (reg.); 15°F; montbell.com