It was -10 on my first night with this bag. It was not perfect but was what I was looking to have in a bag. Sleep is obscure but rest is the objective. I suspect warmer temps will make this the perfect bag for me.
I sleep on my side and decided if you sleep on your back it would be a great bag, on your side it is a good bag but not great.
This review was written in the old system and had content requirements that are different than reviews written today.