A down sleeping bag has its problems. They are usually more delicate than bags with synthetic fill, for example. They also lose almost all of their insulating ability when they are wet. Of course, you could just treat them gently. My own down bag is over ten years old now, and has no tears and no substantial loss of down. I have slept in some pretty rough conditions with it too. Pay attention to anything sharp or abrasive and even the most delicate bag can last for a decade or more.

I have also managed to keep my down sleeping bag dry during some nasty conditions. I once backpacked for seven days in the San Juan Mountains of Colorado when it was raining at some point during every day and every night. My bag never got wet, and I was sleeping under a tarp the whole time. So you can keep a bag dry if you try. That takes care of the negatives. Now for a look at the positives.

I don't really buy equipment that often now, so I had to look at what was out there to see if the above claim was still true. It is. The synthetics are getting closer and closer in terms of warmth for the weight of the fill, but they can't yet match down. It may not be a big difference, but for those like myself who like to backpack in the mountains with less than ten pounds in the pack, every ounce counts.

My own bag, by the way, weighs just 17 ounces. It is rated down to 40 degrees Fahrenheit, but I have used it comfortably below freezing many times. It is from Western Mountaineering.

Perhaps a bigger advantage than the weight savings (those synthetics are close, after all), is space savings. None of the synthetic-fill sleeping bags can pack down anywhere near as small as a down bag. Mine is the size of a loaf of bread when packed. This makes a difference when you have a small pack or a big trip. In fact, I take advantage of the space savings and do over-nighters with a day pack - something I couldn't do with a less compressible bag.

Finally, down sleeping bags last longer. The best synthetic fills seem to start losing loft after just a year or two, and they can't be reconditioned much. A down bag, on the other hand, can be fluffed up in the dryer and may have most of its loft even after ten years if stored properly (unstuffed).

There are certainly times and places for the synthetics. You might not want to backpack in the Olympic National Park's rain forest with down, for example. But if you have to choose just one bag for all-round use, and you like to go light, you should seriously consider a down sleeping bag.