I use them and I love them. They hold very nicely and help hold your points. You can pin on each side of 1/4 inch seam allowance and leave pins in right up to but not going over they are easy to pull out and don't shift the material. I used them to do the attic windows quilts. I don't use anyother kind of pin when I am trying to line up seams or make points meet.
BillsBonBon