Backcountry Gear has the Marmot Atom (long) on sale for $187. Seems like a great deal for a bag that normally runs $249. Pertex Quantum and 900 fill seems to indicate top-of-the-line materials. It is rated to 40 degrees, but in a bivy or tent, it has to go lower than that. I noticed that Marmot has the weight for the 6'6" model pegged at 20 ounces where the site selling it has it at 24.