I see nobody here has said the dreaded backing word "sheets". I use good quality cotton sheets all the time and can't see any reason not to. I only machine quilt and prefer the patterned ones as they do hide imperfections in your quilting. I can find single sheets here often $10 or less as we have a small unique store that handles returns, rejects, overruns of sheets and bedding of all sorts from Sears, The Bay and Bed and Beyond. Last week I bought King Size cotton sheets at $6.99 and flannel ones at $4.99. My friend has done a couple of my quilts on her long arm and had no issues with my cotton sheets either. At those prices, I doubt if I will ever piece LQS 42" yardage at $14.99 a yard and up for a back.