If you only quilt on one diagonal, you have to be careful that the quilt doesn't get pulled out of shape because all your quilting lines will be on the bias of the fabric. I would quilt in one direction, turn the quilt then sew the next line. In other words, don't start each line of quilting on the same edge. Use a walking foot if you have one. I also agree that either quilt you are looking at can be quilted in one direction.