REI Polar pod +20
Only $79 for a backcountry bag? We were skeptical, too, so we sentenced this sack to five months of hard labor with a cash-strapped college student. Verdict: There's nothing cheap about the performance. Our guy took the Polar Pod on winter treks in the Grand Canyon and a coast-to-coast camping trip, plus nights crashing in friends' yards. With generous room through the shoulders, a full-length draft tube, and an adjustable hood, this mummy proved true to its rating. And in drippy forests, the ripstop nylon shell shed moderate moisture. Bonus features: a chest pocket and pillow sleeve. Tradeoff: It's heavier and bulkier than the others here. If weight and space are a priority, spend twice the money and carry half the load with a down bag. $79; 20°F; 3 lbs. 7 oz. (regular) (800) 426-4840; www.rei.com.
Kelty Sonora 20
Prone to cold toes? The Sonora comes in a gender-specific women's model that has extra insulation in the feet and chest, and is roomier around the hips; all versions have a pocket in the footbox to hold heat packs. During a week in the Sierra, our cold-sleeping tester stayed plenty warm when temperatures dipped to freezing, thanks to a generous amount of Polarguard 3D insulation that always lofted up. But any bag worth buying should keep you warm at its promised rating. She called the Sonora "downright plush" for its perfect cut, with just-right wiggle room, and no cold spots when she curled up on her side. The fat draft collar and zipper tube seal in heat. On damp nights, condensation rolled off the nylon ripstop shell. $100; 20°F; 3 lbs. 5 oz. (women's long) (800) 423-2320; www.kelty.com.
The North Face Blaze 3D
Finally, a budget synthetic bag that doesn't claim half the space in your backpack. Like the Sonora, the Blaze is stuffed with resilient Polarguard 3D insulation, but it's a hair lighter and packs smaller; give credit to a tapered cut, featherweight taffeta shell, and a no-frills, no-draft collar design. And nothing is lost in warmth. After a snowy night in northern Arizona, when the mercury dropped near the bag's 20°F limit, our tester bragged, "I didn't wake up once." He credits the coziness to an overstuffed, snagproof, full-length draft tube and a hood "that felt like a pillow." The shell repels mild condensation. The Blaze's narrow footbox is not for sleepers who like lots of leg room, but it's ideal for budget-minded, cubic-inch-counting backpackers. $99; 20°F; 3 lbs. 1 oz. (long) (800) 447-2333; www.thenorthface.com