I also use a scant 1/4", though I have to be careful as I often go just a tad scanter than I should. I piece mostly on a straight stitch machine with a narrow foot, and if I can see about 1/16" of fabric sticking out, that is where I need to be. There is a 1/4" mark and when I sew, I am lined up so that the mark is just visible. I need the fabric to the line, not on the line.
I've tried 1/4" feet, but then I need to line up the fabric with the edge of the foot, and I can't see if I'm going too narrow (which I tend to do). I'd rather be able to see a bit of fabric and then I know I'm where I need to be.