I have the 1/4" for each machine and that helps. BUT I went to a "Spicy Spiral" quilt class and forgot that foot but had the seam guide. Well, when I put it on didn't realize the screws weren't secure enough and was doing about a 3/8" seam. I had already done a lot of sewing so just kept it at 3/8". My table runner was smaller than the others in the class but looks okay and you'd never know I screwed up!