Hmm, that's interesting that you were cold, Tim says they are already over stuffed, so his 30 quilt should be good into the 20's I would think. I usually hit some 28-30 degree nights in August in the Sierra during my week long vacation trips. Sleep comfort can vary from trip to trip. I was out bping Saturday night, checked temps for where I was going that AM. Low was supposed to be around 32, so I took my summer bag, a WM Caribou 35 degree bag. I figured if I added my wool underwear to compensate for any snow or freezing temps, I would be fine or get by. I also wanted to recheck my theory that when it rains, you are colder. I was correct, I was colder. One of my worse nights I think I have ever had and may have been part of the BD Hlight tents drawbacks. It is not waterproof, but almost water resistant. A few tiny pools of water this AM. More experience under my old belt.
It was 27-28F this AM.
Duane