Hi terrywaldron,
Sorry to ask obvious questions but if you are having the same issue with 2 reputable cutters it seems necessary.
Have you measured the dimensions of your cut soaps? If the cutters are faulty then the soaps would have significantly different sizes. Depending on your mould, the tops will probably be the only part of your soap bars with a variation if they are textured.
Are you doing much in the way of colouring, swirling, additives etc.? I've never checked this but it seems probable that, if you are swirling, splitting the batter etc., there might be a different density in each element that could account for some variation between bars depending on how much of each is in an individual bar.
My Scottish blood runs cold at the thought of you spending more money to fix the wrong problem.
Cheers, Grant.