You are all right about the FW, 201, 15-91, 301 Singers for straight stitches, but the cheapest one I have run across is a Spartan (heavy heavy heavy), but so quiet and totally dependable for the 1/4 inch--I think mine has the marked plate, but I am not real sure about that--I don't have much trouble with keeping my seam at 1/4 inch after I work at it a minute or two, I don't need the indicators anymore. But I can't depend on keeping my seam true at 1/4 inch on my newer machines with the zig zag foot, even when I put the straight stitch foot on them. Like they are saying above, it depends on the individual doing the sewing (and maybe her speed, I am not a speed demon on a sewing machine).