The sleeping bag seems to be of ok quality. Tested at 3-6 degres Celsius. Was warm at first, but got a bit cold during the night, so a bit sceptical about -20C spec. The bag is waterproof yes, but lacks the breathability. Probably the reason why I got cold, because of sweat. The fit was a tad too small for me width wise. The length was exact for me, I’m 174cm. Could have had at least 10cm more to add som protection at my feet or add some extra isolation. The collar for shoulders was to thin. Little down and uneven filling so did not work properly when tightened. The zipper is of good quality YKK, one that you can flip over on both sides - but could have had an extra loop/string to make it easier to pull. The down filling feels good and gains air fast. No noticeable smell. Same material inside as outside, so use a sleepliner for better Comfort. The weight is correct.
Sleeping bag a bit thin I doubt warmth claims.