What do you think I am, a scientist? That would take some pretty complicated number-crunching, featuring elaborate graphs plotting the curves of price, weight, and performance to divine the ideal intersection of the three lines. Because warmth is in part a factor of weight, a heavier bag is a warmer bag. Weight also is a factor of price—pay more, get a lighter bag in the same temp rating. Now I’ve confused myself…
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Two examples, though: You could, for instance, purchase Valandre’s La Fayette 550. It’s an exquisitely made down-filled bag, rated to five degrees, which weighs a mere two pounds two ounces. That’s the lightest bag in that temperature range that I’m aware of. But, for the privilege of sleeping in it, you’ll pay $539 (www.valandre.com). Or, you could purchase a Goliath 3D bag from The North Face. It’s rated to zero degrees Fahrenheit, and costs only $179 (www.thenorthface.com). But it weighs nearly four pounds.
In between you’ll find all sorts of good bags. Western Mountaineering’s Antelope Super MF, for instance, has a five-degree rating and a very respectable weight of two pounds seven ounces. Cost: $385 (www.westernmountaineering.com). I’d say that’s right in the cost/performance/weight sweet spot. Same for Feathered Friends’ Ibis, a zero-degree bag that’s slightly heavier than the Antelope—two pounds ten ounces—and costs just a touch more ($390; www.featheredfriends.com). One wild card would be Mont-Bell’s Super Stretch Down Hugger #2 ($300; www.montbell.com). Although it has a “comfort rating” of about 25 degrees, meaning you’ll be very toasty, Mont-Bell bills it as capable of keeping you healthy down to five degrees. And it weighs just one pound 13 ounces. A formidable competitor in this arena, I’d say.
More sleeping bags reviewed in ϳԹ‘s .