remember the excess will be cut off after the quilting is finished- before the binding- so what ever (design) you decide to do on the back may have part of it cut off- and not necessarily evenly- the (process) of quilting draws the fabric up-just like when doing applique or embroidery- how much is dependant on the amount of quilting- sometimes after the quilting is done the quilt is a (little-off) not square anymore- and you lay it out and square it-then add the binding.