I have a Gammil longarm and you can stitch in any direction. You can notice a difference in stitch's if you go left to right vice right to left. BUT, the only time I have really noticed this was quilting on a white top with a black top thread and a red bobbin thread. If you use the same thread on the top and bobbin you will never notice the difference ( I think it has to do with the tension and how the thread is wound)