I have a Janome with a 1/4 inch foot, and I come out with exactly a 1/4 inch seam. Problem is, most patterns now call for a scant 1/4 inch seam, especially if you're doing complicated blocks and stars. If you don't use the scant 1/4", your block will be too small. As far as I know, no one has come up with a "scant 1/4" foot". That means it's back to fiddling with the machine to find a way to feed the fabric into the machine so you come up with the size seam you need. Oh, hum. I was doing that over 30 years ago! I guess we can thank the rotary cutter, or so I've heard, as due to their precision, we have no "give" in the size of the cut. Or something like that.