I now make parts for different people who e-mail/fax me drawings so I
can quote on them.
Some parts are such that I can't tell what they are or what they're
the purpose of them are.
Sometimes I see dimensions as obviously imperial ones, sometime it is
hard to tell, especially when I have NO clue what these parts are.
Personally, I don't give a rat's ass what system is used as I work in
both metric and imperial.
But what seems to be the reason for the US hold-out to stay with an
archaic system?

http://img200.imageshack.us/img200/9974/metricmap.jpg