Super Stretch??

The inner baffles are attached to the outer baffles with the same stretchy material. Thus when the inner baffles are pulled into you the outer shell of the bag is pulled along with it and vice versa.

The baffles don't collapse when you’re just ling in your bag. Conversely when your stretch the bag out (ie get into a cross legged sitting position) you do compress the baffles.

I personally own an UL SS Down #3 and find it to be a great bag with a spot on temperature rating. It is very easy to move around inside the bag without feeling constricted.

I hope this was helpful.

nm

Warmth is subjective, of course… but reading different posts over the years, certain brands develop "patterns" of over or under stating their bag warmth.

I have 2 MontBell "UL down hugger" bags (i.e. not the super stretch version) and my experience is that MontBell ratings are spot on. With a small handful of exceptions, most users report similarly.

In contrast, again with only a small handful of exceptions, most WM users report that their bags are actually warmer than stated.

It's been my experience that the outer stretch baffles of Super Stretch series DO constrict loft somewhat, resulting in leaky seams. This is a byproduct of the design and is not based on manner of use. It's also in contrast to the MB Alpine Hugger series, which incorporates stretch baffle seams on the inside face only. The SS bags are more size adjustable, but the Alpine bags, I find, are warmer. YMMV.

One would think that folks "needing" superstretch bags would have their own built-in insulation.

*Wink*wink*wink*wink*wink*wink*wink*wink*wink*wink*wink*

Oh dear Ben, you are naughty. Maybe they are just skinny little restless sleepers, or want to use it as a 'two person' bag/quilt…

nm

Yum. Chicken soup noodles for me tonight.

>>Brett's avatar?<<

Smokey sez: It's actually a small bike.

LOL! Good one.

David Ure is a bad man. An instigator.

>In contrast, again with only a small handful of exceptions, most WM users report that their bags are actually warmer than stated.

Yes, just looking at the specs, I don't think I would personally choose a superstretch, A #2 weighs 1lb 12oz with 14oz fill and an alledgedly accurate temp rating of 25F. A WM Versalite weighs 1lb 14oz, has 20oz fill and a conservative rating of 10F. 2 more oz for at least 15F more warmth…To me, the difference in 'stretchiness' would not outweigh the total weight:warmth difference.

Allison:

For those who don't need a lot of space, both MB's non-stretch bags and WM's UL slim-cut bags are hard to beat!

To me, a MB SS bag makes sense for bigger folks (or folks who thrash around a lot) — when the alternative is buying heavier "full size" bags.

But all said and done, it's pretty hard to go wrong with a WM — except for that ugly red Summerlite. :)

>For those who don't need a lot of space, both MB's non-stretch bags and WM's UL slim-cut bags are hard to beat!

Agreed, that's why I compared the Super Stretch to a Versalite (wider girth) instead of an Ultralite.

>To me, a MB SS bag makes sense for bigger folks (or folks who thrash around a lot)

And couples…we mostly used our Versalite as a summer quilt for two. Not sure how a Super Stretch would work in this application as I imagine it would shrink to it's smallest size if just layed open on top like a quilt?? What is it's minimum girth??

I believe both Versalite and Ultralite are slimmer cut mummy bags in the “ExtremeLite” series — although of course, the Versalite does have a wider girth, being designed for colder temps. I think it might be “fairer” to comapre the SS to WM’s semi rectangular bags (not that I actually have).

MontBell’s website shows both min/max girth for its various SS bags.

Anyway, enough talking, it’s time for action!

Ben.
The Gear Enabler.

One point about the loft being lost when the baffles are stretched all the way out… that it true… yes… but you are mostly going to be stretching the baffles when you are moving around or having a little stretch inside the bag… etc. For me anyway… when I'm sleeping… my legs are pretty compact (together). It's only when I wake up and want to stretch a bit… flop a knee out the side for a minute… etc… that the baffles stretch way out. Then I go back to a "normal" sleeping position.

With the Super Stretch series only, I find that loft is compromised even when the bag is in a relaxed position. The elastic baffle thread contracts to a linear dimension smaller than that of the outside baffle face, which limits the amount of down that can occupy the boundary zone between baffles. In effect, the bag design offers the complexity and higher price of box baffle construction with the limitations more common of inexpensive sewn-through construction. This may sound like hyperbole, but my cold nights spent tossing in an SS bag – versus comparably rated, standard box baffled bags – were anything but.

Brett,

Please provide a link to one peer reviewed scientific source that substantiates your position that a minor reduction in loft in exchange for a proportional increase in density reduces the insulation value of a down bag… It is an "old wives tale".

Dunno. Probably not a conspiracy, you're right. Ain't much down near the seams, though – dense, lofty, or otherwise.

It's not that the down is compressed at the seams, so much as it doesn't like hanging out there.

nm

I have been nothing but happy with my MB Super Stretch #2 and #3. I am 155 lb (70kg) and 5"9' (1.75m). I'm a side sleeper and tend to wake and turn over several times a night and I love the stretch in these bags.

Apparently I have been brainwashed to believe that since the inner lining hugs the body and decreases air spaces I will be warmer. Since I have bought into that MB line I find that my bags ARE warm and the temp ranges accurate.

As Richard notes, after a certain point increasing the density of the down in the same space does not make a bag any warmer, though I can see how that space might be less compressible. Anyway MB makes a great bag as does WM.

I think that to imply that MB is under filling and being less than honest about how warm their bags are is misinformed. However, as I mentioned, I am brainwashed.

So for now I will continue to believe that the MB bags are great bags. If I stop believing then I will have to pony up the $ for the WM bag that Ben is try hard to enable.

Pass the Kool-Aid, please.

-Mark

Mark – the placebo effect is for real! I'm sure there are peer-reviewed studies proving it, too. *vbg*

Anyway, warmth is subjective of course, so no stepping on toes there nor feeling stepped upon, we hope. Gotta compare apples to apples, or rather the same apple tester needs to taste more than one.

"The same apple tester needs to taste more than one."

Brett — very well said. Mark should buy a WM (we know he wants one) so he can compare with his beloved MB SS and report back to the community.

Ben
The Gear Enabler.

nm

>I believe both Versalite and Ultralite are slimmer cut mummy bags in the "ExtremeLite" series — although of course, the Versalite does have a wider girth, being designed for colder temps. I think it might be "fairer" to comapre the SS to WM's semi rectangular bags (not that I actually have).

I'm not sure I follow the logic. The SS bags are mummy bags, not full zipper rectangular bags. The Versalite is 3 inches larger in girth than the Ultralite making it pretty spacious as mummy designs go.

If you are big enough to use the full maximum girth of the SS bags, then I think you will find that you are effectively stretching the total down over a larger area than a smaller person, thus you would not be as warm in the bag as a smaller person. So I would say that wide people (not necessarily fat as some folks just have wide shoulders or hips) might be better off getting a bag that fits them nicely without envoking stretch technology. Or getting a warmer version of a stretch bag to compensate.