Metrics do make math and science easier. No question about it.

Hell yes. A measure of unit greater is 10 times greater. It's predictable.

How many inches in a foot? Uh... 12. How many of those in a yard? 3... How many of those in a mile? 1760...? Say, how much is an oz of honey? Uh, is that a weight measure, or a volume measure? Alright, so let's add up the following measures: 1½"+2'¾"+½"+...

If you grew up in it, you've probably learned it by heart over time. However, it's completely arbitrary and those who did not grow up in the system cannot anticipate how much the next unit of measure will represent. Using fractions also adds a level of complexity, especially for those not particularily skilled at mental calculations.

I hate the imperial system. Ask me how tall I am, though, and by force of habit I couldn't tell it to you in metric to save my life.