There are right and left stitching guides that slide into the back of the walking foot but they simply ride in a slot there and are not able to be fixed in position. While this makes them easily adjustable, it is also almost impossible to avoid nudging the guide while repositioning the quilt. This flaw means the distance one is trying to set for the next row of stitching constantly needs to be rechecked. After struggling with the guides for several rows, I switched to the painter's tape method. Much better!
I've taken to keeping my Supreme Slider on the sewing surface even when not free motion quilting. It does seem to make whatever is being sewn move along nicely.
Luckily the tension has been no problem so my stitching did not look like this jet trail!