I couldn't find what I was looking for in the search functions, I am sure someone has done this, I have a -30 degree LLBean sleeping bag it is huge for me but is really cozy and warm, I have had no problems sleeping in 20 degrees with it and a pad under. I was thinking of putting a hole in the foot end and using it like a tube to get rid of a pad . Before I damage the bag I was wondering if anyone has had any luck using a bag as an all around under and top quilt. I was thinking of using some velcro on the botton part to keep it from falling on the ground . The bag weighs 4 lbs and does not pack really small but to get rid of a pad would be worth it to take backpacking