Yeah, yeah, but the day after you pass certification for using it, you'll stumble over a Jowett Jupiter or Armstrong-Siddeley Hurricane at a price you just can't turn down, and then you'll need to get the Whitworth model.
And don't forget, if you work on old machinery, that you need the model for square nuts/capscrews. The wrenches for hex nuts won't round off the corners on the square nuts nearly as well as the correct model.