Doesn't #4 in the FAQ answer your question from the link above?

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Is the VP-C01 cleat compatible with other brands of clipless pedals?

Some cyclists do seem to find VP-C01 usable with certain pedals made by other companies. However VP-C01 is designed to be compatible only with VP pedals (see "Which cleats are compatible with my VP clipless pedals?" FAQ). VP cannot guarantee compatibility with any other pedals and is not responsible for any problems that might arise by using VP-C01 with pedals other than those recommended.
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From my personal experience, I've had some non-Shimano brand cleats work with my different sets of SPD pedals, but I had to readjust the tension on the pedal every single time if I went back to a Shimano cleat. In my case, the cleats aren't exactly the same, but it's pretty annoying to change setups on different bikes based on different cleats. At the end of the day, I stuck with Shimano cleats for the convenience. I've often wondered if the other manufacturer has to change the tolerances of the shape in order to avoid some kind of lawsuit. Maybe someone else knows more?