I use sheets all the time and can always find King sized cotton or flannel sheets for less than $10 at Lens Mills or Giant Tiger (only in Canada). Sears also sells single sheets. Sheets machine quilt up just fine, wash and wear well. I would hate to use yardage often $10 to $15 a meter here when I would need 5 or 6 metres for a large quilt. I stock up on sheets when I find them on sale and buy colours that I know will work out for the scrap quilts I usually make.