For the shoulder seasons and for some winter camping situations, many hikers prefer to use a sleeping bag with a temperature rating of 10-20 F (-12 to -7 C). Others may prefer a warmer bag like this for summer backpacking in the mountains, simply to ensure they don't get cold. While the latter group could benefit from our lightweight philosophy, as explained for sleeping bags in our article: Ultralight Three-Season Down Mummy-Style Sleeping Bags: State of the Market Report 2010, both groups can save weight by carrying an ultralight sleeping bag.
Sierra Designs claims their Vapor 15 is the lightest 15 degree down mummy-style sleeping bag on the market (we will check that out in this review). The Vapor 15 sets another landmark for Sierra Designs - their first bag featuring 850 fill power down - rivaling bags from Marmot, Feathered Friends, and Western Mountaineering. What is there to like and dislike about the new Vapor 15, and how does it stack up, by the numbers, to comparable bags?
ARTICLE OUTLINE
- Introduction
- Description
- Performance
- Comparisons
- Assessment
# WORDS: 2580
# PHOTOS: 7
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Discussion
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Companion forum thread to:
Sierra Designs Vapor 15 Sleeping Bag Review
A very thorough review. However, I'm a side-sleeper and a restless sleeper. I need a bag that has some flex to avoid feeling like I'm being held hostage in my sleeping bag. If this bag had the Sierra Designs flex, I might consider it. I will continue to save up for a Mont Bell Super Spiral down hugger bag instead.
Something seems to have gone awry with your metric conversions: a centimetre is approximately 2.54 cm therefore;
5'10" = 177.8 cm (usually rounded to 178 cm, not 180/1.8m)
6' = 182.88 cm (usually rounded to 183 cm, not 180/1.8m)
6'2" = 187.96 cm (usually rounded to 188 cm, not 190/1.9m)
"I have not personally tested any of the other 10-20 F (-12 to -7 C) rated bags in the table above, so I canβt compare them other than by the numbers. One main difference is the Vapor 15 has a half-length zipper, while the others all have a full-length zipper"
The WM Versalite also has a half-length zipper.
Thanks for the excellent review, Will. It's great to see another manufacturer moving further in the direction of ultralight, high quality gear.
In discussions of bag length, I don't think I've ever seen acknowledgment of the importance of foot length, and ankle extension. A person with a longer foot, and a looser ankle, will have an overall body length considerably longer, when lying on their back, then someone with a shorter foot or a "stiffer" ankle. So in a shorter bag, a longer-footed person will more easily have the feeling that the bag is too short, as they feel their toes pressing agains the foot of the bag, and their head against the hood. I've never done the research, but I'll bet the difference between a stiff-ankled size 9 foot and a loose ankled size 11 foot could be easily two inches.
Another thing to note, though I haven't seen the Vapor, is that the Marmot helium is, as I remember, generously cut (i.e, large cross-sectional diameter), and the vapor looks more compact, judging from the photos. So the average down density per square inch of bag surface, which is, I think, more important than the total down in a bag, might favor the Vapor.
The zipper on the WM Versalite is definitely full-length, as it is on all their bags other than the Highlite. Considering the Vapor 15 is essentially the same price ($440 for the SD, $455 for the WM) I believe the Versalite is a much better value. It's performance is legendary in this community.
Yup, Versalite has a full length zip. I believe it's an MSRP of $440 though for regular length. Of course, you're far more likely to find a deal on the SD bag for what that's worth.
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