I have used old mattress covers as batting frequently. They make a very warm, heavy quilt. Since the usable part is the size of the top of the mattress, the quilt will not be large enough to use on a bed. They make excellent throws or cuddle quilts for older children and adults or floor throws for babies. I have machine quilted them, but it's not necessary. I prefer to tie them. It only takes a few ties, as the mattress cover is already quilted.