Kaufman Kona bleached white Muslin is fantastic to use in a quilt... I buy this by the bolt to have on hand when I need or want to use white fabric as a background in my quilts. It is one of the few fabrics that really does match from bolt to bolt in case you run out and need to purchase another piece.
I just checked fabric.com and the $4.98 Premium Kona Bleached Muslin is made by Kaufman so it is quality fabric.