You should consider a few factors when making this choice: the climate in which you do most of your camping, how far into the shoulder seasons you plan to camp, and whether you are a warm or cold sleeper. Our most popular choices for a three-season Elite Series bag are the Palisade, Alsek, and Sawatch. The Flex Series offers more ventilation options in the foot box, and the Flex 30°, Flex 22°, and Flex 15° are the most popular in that category.