I recently went on a snow camping trip with only my Big Agnes Lost Ranger and a thermo-rest ridgerest pad. The temps were in the high teens and I stayed warm with my belay jacket and pants on, however, I noticed a good deal of frost on my bag which was expected since I was sleeping in a 3 season tent. I’ve read about the Montbell Breeze Dry-Tec Ultralight Sleeping Bag Cover as an intrical part of a sleep system but I was wondering if anyone had any experience with the bag cover. The weight looks good but I was wondering if it would add any warmth to the bag and to help reduce frost. Also, what is the condensation like when using the bag cover. I like the weight and especially the price of the bag cover compaired to some of the other bivys. Any thoughts would be appreciated.