MontBell UL Super Spiral Down Hugger #3
$339, 1 lb. 7 oz. (regular), $359, 1 lb. 9 oz. (long)
Sizes: regular and long
We tend to buy a sleeping bag based primarily on temperature rating, price, and weight, ignoring a key characteristic that will affect how well you sleep in it as much as its warmth: comfort. I’ve slept in many bags—especially ultralight models—that are cut so narrowly to shave grams that they felt like a straitjacket. Montbell’s UL Super Spiral Down Hugger #3 provides superior comfort through a simple but unique feature: elasticized baffles that stretch and contract with your movements. The bag effectively acts like a second, much thicker and warmer layer of skin, moving wherever you move without inhibiting you at all.
With 11 ounces of 800-fill power down, the bag carries an EN rating of 40° F for comfort, 30° F for men’s comfort, and 3° F for extreme (read: survival). I tend to sleep warm and found the bag warm enough for nights around freezing. Only on my coldest night in it did I have to pull on more than a base layer top, socks, and underwear: inside a yurt in Idaho’s Sawtooth Mountains in early April, when we let the woodstove fire die out overnight and woke up to an inside temp of 18° F. At Idaho’s City of Rocks, I did not close the bag up entirely on nights in the 40s, though I pulled the hood over my head on nights in the low 40s in Oregon’s Eagle Cap Wilderness—but still only wore a T-shirt and underwear. Yet the bag was not uncomfortably warm on nights that did not drop below 50° F in Idaho’s Smoky Mountains. More than its warmth and low weight and bulk, though, this may be the most comfortable bag you’ll ever saw wood inside. Looking for a less-expensive alternative? Go for the Super Spiral Down Hugger #3 ($249, 1 lb. 15 oz. for a regular), which uses 650-fill down instead of 800-fill.
For more reviews of my favorite sleeping bags, type the words “sleeping bags” into the Search box at left. See also my Pro Tips articles “How to Choose a Sleeping Bag” and “Staying Warm in a Sleeping Bag.”
NOTE: I’ve been testing gear for Backpacker Magazine for 20 years. At The Big Outside, I review only what I consider the best outdoor gear and apparel. See all of my reviews by clicking on the Gear Reviews category at left or in the main menu. See more reviews of backpacking gear I like by clicking on the “backpacking gear reviews” tag in the tag cloud in the left sidebar.