Daniel Neilson braves the cold to test some of the warmest sleeping bags on the market. On test Marmot Plasma 0 sleeping bag

This lovely, soft down Marmot bag is easily one of the best tried, up there with the PHD and Mountain Equipment bags. There are just a couple of details that I prefer on the other ones. I used it quite a lot over last winter, and have been impressed with the comfort overall. It has a whopping 875 fill power, giving it a great warmth-to-weight ratio with a comfort rating of -8°C and it weighs only 1243g. One key difference is the vertical baffles that are designed to eliminate cold spots, and it seemed to work well. I would have liked a thicker baffle behind the zip, and the pull cord around the face to be accessed more inside the bag. The Pertex Quantum outer is best in class here for water resistance. Overall, an excellent bag, but just pipped by the Mountain Equipment one.

Reviewed in January 2015 Issue