At 24 I hope I can still qualify as a "younger Canadian". I've never been taught anything in school (engineering) that was imperial (although I did have a materials science professor give us an exam in imperial units, after the rest of the course was metric...jerk) but whenever I would work on stuff around the house with my dad, everything was in imperial. That combined with golfing a lot when I was a kid lead me to have a pretty good grasp on inches/feet/yards.

Does anyone else change the systems based on the length of something? For example, I would say 100km instead of "about 60 miles" but I'd say "about 100 miles" instead of 160km.

One other thing I've found odd is that in Europe no one knows their running pace, they know the speed. So 5:00/km is meaningless, whereas in Canada/the US runners always talk about paces in time per mile/km.