mines a eureka 40* so same thing when its cold. i dont know what you use but i found these a while back and simply put, awesome. i use it by itself sometimes.
i have the emergency bivy and i think i'm gonna buy the utility blanket
my bag and this bivy fit into the top kidney bag, everything else doesnt fill the two side bags, you can see in the pic even though i packed some extra clothes the sides at the compression straps are totally empty
for summer i made a sleeping bag out of flannel sheets, i can do overniters comfy with nothing more than a kreiga r15.
go light go fast was kinda my motto before you clowns stole it