It doesn’t get much better than the kryos - Mountain Equipment Kryos Sleeping Bag, Left Zip

Last year I needed a bag for an early winter backpacking and climbing trip to Wrangell St. Elias and the Chugach Range in Alaska. I could have gotten a down liner for my other bag: the also superb Sea to Summit Spark III, but didn’t want to carry two bags and at the time, campsaver was running an incredible deal on this bag with the addition of a $100 gift card. I pulled the trigger and was thrilled with my initial impression of the bag. I previously had a mountain equipment glacier 700 bag that was stolen but also a top notch bag, so I knew what to expect. The bag is incredibly lightweight for its temperature rating and the quality of down allows it to pack down extremely small for a sub zero rated bag. The internal part of the bag features something like horizontal elastic baffles that keep the space in the bag very cozy and thermally efficient. The footbox if great and allows you to not feel like your feet are being smushed. The zip action is smooth and it features a very functional draft tube which allows it to keep out the freezing cold while keeping the ripstop shell from getting caught in the zipper. There are adjustable pull tabs for the hood and collar of the bag and internally there is a nice baffle that comes in close to the chest to keep that warm air in. Mountain equipment also features magnetic lode locks towards the top of the zipper which brings the bag in nice and close to shoulders and neck as well as keeping the zip from coming undone. The shell fabric is pretty incredible as well. It manages to be extraordinarily lightweight yet still has somewhat of a durable feel to it and best of all; has greater than 1,500 hydrostatic head while still being breathable and not making the bag a sweat box. I could easily go on and on about all the features of this bag and list tech specs but I’ll just say that in this performance category, you’ll be hard pressed to find a better performing bag no matter the cost.