The 3-season Sierra Designs Backcountry Bed 600 bag offers a truly unique design, creating one of the most comfortable and bed-like feels of any sleeping bag we have tested. The Backcountry Bed features no zippers, toggles or Velcro flaps of any kind, but instead offers a large "U"-shaped opening that is covered by a down flap. This down flap acts as a quilt. The quilt not only helps regulate temperature extremely well, but it also offers unmatched freedom of movement for the user's upper extremities, making tummy-sleeping as comfy as it gets.
For all its comfort advantages and range of temperature versatility, it is a little on the heavier side, and does not offer supreme compressibility. While we thought the Backcountry Bed was super comfortable, our testers found the Nemo Salsa won overall, offering more comfort for "high-knee" sleepers. The Salsa was around a pound lighter and much more compressible. That said, the Backcountry Bed 600 for 3-season use remains a rad option for someone seeking its unique advantages that few other bags can even think of offering.