I love, love, love using a solid backing. But I LAQ and adore how a solid muslin shows off the quilting stitches. Or any solid for that matter. But I most often back my own quilts with whatever whim comes my way that day. Many of my quilts are basically double sided. I have pieced backings with leftovers and orphan blocks from the front adding big blocks of fabric to fill it out. But I have a sizeable stash of wide backs right now that I will start digging into very soon. Even though the price of a wide back is shocking at first glance (averages around $14 per yard on Thousands of bolts), once you do the math you quickly realize it is much more cost efficient to go 108" wide. For a queen size you only need 3 yards. When using standard 44" wide fabric you need 7 or 8 then you have to piece it. The final price will often work out to be more when using a coordinating LQS quality fabric for the back and that isn't even considering the cost of your time to cut it, square it up and piece it and thread used. I am considering buying a bolt of 108" wide muslin just to have it on hand for backings and to use on fronts as well.