We're also on the metric system herein the UK, but I always change it to Fahrenheit because I still think in Fahrenheit even after all these years since the change and also it's easier for the USA to understand on the forums...
Today our temps are 11 deg c... around 60 deg F...and here in the Uk a quarter pounder is called exactly that. When we first changed to the decimal system there was all sorts of suppositions about how things like the ''quarter pounder'' would be changed, but it didn't happen!!
However, what did happen , and I'm still ashamed of our country for it to this day, was that retailers were fined, some even jailed ( small retailers like the market stallholders selling fruit and veg) for not displaying their prices in Kilos instead of pounds and ounces... it was a disgraceful time in our history...and I hope when we leave the European Union in a week's time that we can go back to using the imperial measurements..I bet we can't tho' !!