I would not use a sheet if I wanted if the crinkled vintage look that requires the shrinking of cotton to obtain. But there are many quilts where I don't want that look, and they are usually the not-hand quilted ones anyway which are good candidates for a sheet backing. Flannel sheets are almost all cotton, and I think flannel backings are a must for baby quilts because they are so soft and non slippery when used. I look for the adorable sheep or critters or snoopy etc. and not the Christmas or too winter scenic ones. Good Luck.