I am far from experienced, but My son and I are sleeping in the yard tonight and it is going to be low 30's.I have a underquilt but for me but for him I put 2 cc pads inside a wallmart fleece bag and slid it in the WBBB inner layer.Now this is not what you would want on a backpack trip but we will see how it does.He has a 20degree bag on top.Nothing really beats quilts and Once you figure them out they are so much easier to deal with but come at a price as we all know. If it does not work he has the option of going inside if he gets cold.