Hi,
About a year ago, I bought some of the "foldy stuff", and made a table runner for my sister's dining room. Because of the muslin base, it is a thicker item when done. I used a cotton print for the backing of the runner, and it looks fine. I think if I were to attempt an entire quilt done with this "stuff", I would just back it with a cotton or maybe a light flannel, since as you sew the blocks up, they sort of quilt themselves, as they are folded over onto themselves. (Not sure if that makes sense to anybody, but it's the best I can do.) I will admit, it was a fun to use!