In two weeks camping in Sweden me this sleeping bag has always kept warm. Both the tent and sleeping in an open hut I have not frozen. The extreme range I could not test, but after a cold rain of the sleeping bag is definitely good for warming up and it should even be too warm to the zipper easily open on the feet or raise from the top. When you step into the cold sleeping bag, he warms up quite quickly, with the footwell needs longest, which in my opinion but is logical. Spacious he is all because even my friend with more than 1,90m body size can lie comfortably. From me, then go two thumbs up. :-)
