To quote the great (but thankfully not yet late) Dr. Darrol Stinton...
Be ambidextrous in your units.
You'll meet many and various unitary systems around flying machines (or engineering in general), nobody is going to have any sympathy for you if you don't know them. The only thing to do is roll your sleeves up and learn 'em - whatever you grew up with.
Like you I grew up in SI units, but regularly fly in Imperial. On the other hand I gave a lecture at Embry Riddle (an American aeronautical university) earlier this year and did the whole thing in SI - you should have seen the students panic, they'd never seen a Pascal before !
G
Who has been known to do aircraft weight and balance in kgf. inches 
In the meantime I own one aircraft where everything on the engine is in metric, and on the airframe in imperial.