I've been using one since I started FMQ, about 6 years ago on my DSM. It makes a big difference in moving my quilts around for quilting having tried it with and without the slider. I do some fairly large quilts and often use flannel or minkee for backing. I can't say it never moves because it has, somewhat. Enough that I have chewed up the opening for the needle area a little. In the last year or so I have been taping it down with masking tape because I didn't realize that it can be washed with warm water to remove lint and help with stability. Anyway, just ordered a new one from Amazon which comes with a pink foam backing now to help with placement. Can't wait to start with a new one!