When used on the move, it packs downs well ( to roughly the same size as a standard football) and lofts back up in no time at all (especially if you fluff it up as you toss it into your tent).

I used this recently on a sub zero trip to Dartmoor and found it extremely warm and not too claustophobic as same bags can be when cinched up. My advice would be to get a Rab Ascent 500 or possibly 300 for spring/summer/autumn and supplement it with a cheap summer bag for winter. After years of messing about I now use a two bag system that together weighs 1080g and can handle -8deg.Additionally, the zipper along the side of the bag is strong, thick and easy to open and shut, and when operated from inside the bag it rarely snags.

The OEX Leviathan EV 900 is a lightweight and compact 4 season sleeping bag that will keep you warm in temperatures down to around -16°C, and still safe as low as -38°C. The 900gsm / 600 Fill Power duck down in the Leviathan has a fluorocarbon-free hydrophobic coating, which helps it to retain loft when it gets damp, performing better than untreated down. It’s a number that’s based on the amount the down in the sleeping bag lofts back up after being compressed, with higher-quality down lofting up more than lower-quality down. The OEX is duck, the high-end Rabs are goose and the Ascent falls somewhere in the middle with a mixture of duck and goose.Perfectly suited to wild camping, global travel and off-season family camps, this down-filled bag will keep you warm and comfortable when outside temperatures go well below zero. Production and marketing costs aside, one of the key differences is in the quality of the down used.