I looking to upgrade my sleeping bag so I can get more versatility over a range of temps. In particular, a light bag that would be suitable from 50 degrees down to about 25. I have seen ads for bags with detachable covers that offer flexibility over a wider variety of conditions, which seem like a good option for multiday trips. What do you think about this kind of bag? Worthy innovation or a gimmick? Any ideas for some good bags like this in the $125 to $175 range? David Boulder, Colorado
These systems work, but to be honest I'm not terribly enamored of them. I think they're exceedingly complicated, and you end up spending about as much as you might on two straight-rated bags for different temperatures. I mean, once you "buy into" a setup like this, you're committed to buying a bunch more products from the same company. And while Sierra Designs makes excellent stuff, I'd still rather be able to shop around.