It's helps...unless you are one of those people like me who have trouble stitching a straight line! I think it does help in spite of my lack of skills.
Are you talking about an edge joining foot where there is a bar running down the middle of the foot, like one you would use for heirloom sewing? If so, I have one and I use it often...including to join smaller pieces of batting with bridging stitch...either to make fluid larger pieces of batting for quilts or joining ITH embroidered quilt blocks for the quilt as you go technique.. They are not very expensive, they are a standard snap on foot and I find it very helpful, even for in the ditch stitching because the metal guide centers right in the middle of the seam.
I have the same and use it a lot, for all mentioned purposes.
I also have a foot that has a guide at the right edge, which I use for top stitching along the edge of a garment - thin cotton dresses and blouses as well as coats made from thicker material. Love that one too.
The Husqvarna ones are the snap-on type and are relatively cheap.
I got a Bernina 570QE recently; their feet are sturdier and more expensive, but when you sew a lot they are still worth the money.
yes , thanks, i want one will go to my dealer she has found me an flat fell foot also
I love the specialty presser feet. I think of them like cake decorating tips--you can do a lot with one tip--but the other tips help make the cake a work of art.