I wouldn't dare take just the quilt, especially if there's a possibility of it dropping to 0*. I was planning on taking my 30* bag and the quilt to put on top. Ive heard quilts take some getting used to so I figured with my bag at least drafts wouldn't be hitting me directly. My plan was to strap the quilt to my pad so it doesn't slide off then have my bag underneath.
_________________________
My gear is no where near lightweight