Sacks stuffed with water-resistant down now dominate the market.
Sierra Designs Mobile Mummy 800
GEAR OF THE YEAR
The quirky features of the 15-degree Mobile Mummy ($379) are not original, but Sierra Designs is the first to combine them in a way that creates a truly useful bag that can be worn like a jacket. The full-length, two-direction center zip eliminates the contortions required to snug yourself into a typical side-zip bag. The arm ports allow you to read a book without cracking the cocoon. (Flaps seal the holes when you pull your arms in.) While one tester waited for a backcountry cabin to warm up, he slid his feet through the bottom zipper and wore this bag like an 800-fill coat—which he didn't have to pack. From the beanie-like hood to the carrot shape, this cozy bag quickly conforms to changing insulation needs. 15˚; 2.3 lbs
Millet Baikal Extend
BEST FOR: Synthetic diehards.
THE TEST: One tester had only to roll over to appreciate the stretch stitching in the Baikal Extend's ($130) lower half. "Mummy bags usually feel like a coffin," he said, "but I could bend my legs!" He also appreciated the glow-in-the-dark hits on the toggles and zipper pulls. But it was the bag's enveloping warmth that made him happiest—namely, a heavily baffled hood and a double-thick layer of fibers across the body, where you need them most. (There's just a single sheet around the legs.)
THE VERDICT: Not the lightest or most packable, but a steal for the price, especially for active sleepers. 30˚; 3.4 lbs
NEMO Coda 0
BEST FOR: Any temperature.
THE TEST: Yes, there's ample justification for the shockingly high price tag ($700). For starters: stretch stitching in the legs, a DWR-treated shell, and water-resistant 850-fill goose down. Meaty internal draft collars and an overstuffed hood add to the zero-degree Coda's cold-weather chops.
>>Read the full review
The North Face Blue Kazoo
BEST FOR: Easy access.
THE TEST: It's the little things that stood out on the latest version of the Blue Kazoo ($280). At 2 a.m., we appreciated the full-length zipper and glow-in-the-dark pull, which made for speedy exits. The ergonomically shaped footbox gave our piggies room to roam in comfort. When the temps plunged during a backpacking trip in the Canadian Rocky Mountains, the hood cozied up tight and the water-resistant 650-fill goose down insulated true to its rating.
THE VERDICT: All the performance of a $400 bag at a much better price. 20˚; 2.5 lbs
WARMTH TO WEIGHT: 4
SLEEP COMFORT: 4
Mountain Hardwear Ratio 32
BEST FOR: Wet climes.
THE TEST: While the untreated down bags on a rainy test trip became soggy, the 40-degree Ratio's ($230) feathers, which are coated with a water-repellent material, stayed lofty, even when our tent was dripping with condensation. (The water-repellant treatment on the bag's shell helped.)
>>Read the full review
Eddie Bauer Airbender
BEST FOR: Keeping it simple.
THE TEST: If sleeping bags and sleeping pads are always used in tandem, why not combine them? The top of the Airbender ($800) is 850-fill water-resistant down in a mix of horizontal and vertical baffles to optimize warmth and packability. Where your back rests against the ground, Eddie Bauer sewed in an air mattress surrounded with synthetic insulation; it inflates via a hand pump in the stuffsack.
THE VERDICT: No more sliding off your pad. It's a cool idea that could save you a bit of space and weight, but you pay dearly for the convenience. 20˚; 3.1 lbs
WARMTH TO WEIGHT: 4.5
SLEEP COMFORT: 4.5
Sea to Summit Spark SPII
BEST FOR: The weight and size obsessed.
THE TEST: On a monthlong sea-kayak trip down the Baja Peninsula, this 35-degree bag ($360) shone. The 850-fill European goose down crushed to the size of a softball—perfect for cramming into overstuffed hatches. Unleashed, it ballooned into puffy warmth. The desert's heavy dews had no effect—the water-resistant down maintained its loft, and the Pertex Quantum shell dried fast. The cut is narrow, but tester said it wasn't restrictive.
THE VERDICT: Weighing less than some jackets, it's an ideal choice for minimalists. 35˚; 1 lb
WARMTH TO WEIGHT: 5
SLEEP COMFORT: 3
Rab Neutrino 400
BEST FOR: Guilt-free backpacking.
THE TEST: Rab has taken the lead in sourcing ethical down. First, it chose expensive 800-fill European goose feathers, so it could trace the origin of every cluster to ensure the birds were treated well. Next, it partnered with Nikwax to develop a fluoro-carbon-free treatment. To construct the 27-degree Neutrino ($379), it stuffed the treated feathers into a trapezoidal baffle design, added supersmooth zippers, and threw in a drybag compression sack.
THE VERDICT: Exact warmth rating in a compact package. 27˚; 1.8 lbs
WARMTH TO WEIGHT: 4.5
SLEEP COMFORT: 3.5