It wasn't as easy to find testers for budget sleeping bags as it was for the premium models. Our friends were practically beating down the door to try some of the best 900+ fill power down bags. Far fewer were interested in getting their hands on an affordable, 3.5-pound, synthetic model. Nevertheless, compromises were reached to ensure that all budget bags were tested in a range of climates by a group of outdoor enthusiasts with a diverse set of interests and experience levels. Bags were field-tested across four Western states at elevations from -150 to 10,000 feet. Below we discuss how we evaluated each performance metric.
We tried to limit the number of variables when we evaluated sleeping bag warmth. All bags were slept in for at least three nights in the same 48°F room. Careful notes were taken to record the warmth of each bag relative to the others. Our 1-10 warmth scores reflect this relative warmth. In our product reviews, we've also tried to comment on each bag's warmth in the context of its EN temperature rating.
Measuring weight is pretty straightforward. We stripped each bag of its accessory features and included stuff sacks before putting them on the same digital scale. All bags that we tested were size longs that are for sleepers up to 6'6". Note: the Klymit KSB 35 only comes in one size ("regular") but it is long enough for someone up to this height.
Comfort is arguably the most subjective of our performance criteria. To try to keep things fair, we recruited three separate testers to evaluate every bag's comfort. These testers then gave their independent scores for each bag relative to the others. The final comfort scores that we report are an average of the scores given by the three testers.
To evaluate the packed size, we stuffed each bag into the same 15-liter Outdoor Research compression sack. Minimum volume was then measured using a tape measure and simple arithmetic. Although these calculated volumes don't match all of the manufacturers' reported volumes, they serve as a fair way to compare the bags that we tested to one another.
The more ways a sleeping bag can function, the better. We evaluated versatility by considering how well each bag performed when wet and across a range of 3-season temperatures. Extra points also went to bags that can function in other ways, such as bags that can fully unzip into a quilt which could be shared between two people.
Features and Design
Sleeping bag makers are coming up with more and more features to differentiate their bags in the crowded market. Our testers used their significant expertise to evaluate how well these features addressed the problems they were designed to solve. Also, we considered the overall design of each bag and whether it matched its target applications.