The 1/4 inch with guide on my Janome is not a scant 1/4. I think the guide rocks the foot to the right and that makes it more. As long as I'm doing blocks for myself, it usually works fine because I have consistent seams. If I have to make a block to an exact measurement to match a friends block, I don't use it, I use masking tape on the machine bed. So I love it for me, not for sharing with others.
