As free citizens of the free world, we are all free to speak of miles or kilometers, ounces or grams as we wish. We don't need permission.

Money is a different story. I don't suppose you can coerce your bank into doing your statement in shillings and pence.

I remember fondly a story about a man having a pleasure boat built in Ireland. One day the builders came over to his place to convert the measurements "from metric to Christian."