I use sheets all the time on the backs of my quilts. They machine quilt easily, wash and dry well and do not slide off the bed! Most of the quilts I make are for kids or are college bound and are washed frequently. A sheet would probably not be my back of choice for an embroidered hand quilted heirloom but it is great for a scrappy disappearing nine patch. Backings need to be chosen with the recipient and use in mind. Sheets are economical and may be perfect for you.