I have quilts, but I keep pads on the bike in case I have to go to ground or need another layer of warmth. In the past, I have used a square inflatable pad (e.g., exped 9DLX) with another hammock with great success. The square pad helps to hold open the shoulders and foot area. After getting the WBBB, I used a square shaped inflatable pad (the Trekker). There was a little bit of an issue of it shifting in the foot area.
I've been looking at the Peak Elite AC. Does a mummy pad work work better with the WBBB footbox better than a square pad?