Yep I agree - both
its worked brilliantly for me over the last 20907248182351.028089724211549023 Kmh or 48 years if you want to be technical.
I often measure steel with mixed metric and imperial measurements sometime its easier to see an exact mark at 4 inch's than give an approximate mm measurement.
I do think the American system has more merit than the old English measurements like Whitworth etc. Perhaps where we are getting it wrong is trying to standardise. Old aircraft flew and new ones fail due to errors ? Just ignore that small section of aviation history where the comets kept falling out of the sky - funny they still do, the RAF has lost a few in the last 20 years. (otherwise known as Nimrod or comet mk4).
And these are the brand new ones we scrapped with zero hours on the clock (there you go toolmaker a zero for you).