Experiences with 30°F (-1°C) limit quilts for summers in the mountains?
I mostly hike in the European Alps, Pyrenees, Balkans etc. evening temps rarely drop below freezing but it's not unheard of.
I sleep warm, on an R=5 pad, in a tent, and wear alpha 60 base layers.
Based on the Timmermade Alpha 90 blanket adding 10°F (5°C), this should surely add a couple of degrees of warmth?
It seems fairly accepted that a light down jacket will add a few more degrees.
I'm thinking about the Ice Flame Semi Summer NXT quilt with 300g of down and about 1.25" loft. The manufacturer claims this would have a comfort rating of 5°C and limit around freezing. I trust these numbers having used their quilts before.
Based on the above, I'm hoping this will be comfortable in warm weather and warm enough slightly below freezing to sleep well in high altitude camps even in a cold snap.
What are people's experiences with using similar quilts in mountain conditions in the summer?