The benefit of using metric over other systems is in its utility at conversion, since most people don't like to be bothered to have to do math without a calcucrutch.

That's fine and dandy. I can admit that, even as an American, the metric system makes sense, except for one glaring exception that I adamantly refuse to budge on:

Temperature is better measured using the Fahrenheit system.

"But OUR system is based on the boiling and freezing points of water!" they say. SO WHAT? With Fahrenheit the degrees of latitude are more expressive in terms of our own physical tolerances. The difference of a mere 10 degrees means changing from a 20°C jacket to 30°C shorts. If the measurement is based on something so arbitary as the physical properties of water, why not make it more useful by comparing it to degrees of human livability? Fahrenheit accomplishes this nicely. 0°F and 100°F are approximately the lower and upper limits that the human body can comfortably handle, taking into account the normal range of clothing offered to us. It's a realistic, and more to the point, useful measurement.

The benefits of metric conversion are lost on temperature. The only advantage is that you don't have to think when someone asks you at what temperature water freezes or boils (and honestly, when was the last time you cared what the temperature of boiling water was?).