Temperature is a weird one, and shows the difference between 'metric' and 'SI unit'. Fahrenheit is neither, and for me is far from intuitive. Celsius is a metric unit, but it's not the SI unit, which is Kelvin.

Celsius certainly makes more sense on the human scale than the other two - the general public is familiar with 'water freezes' and 'water boils' - but it's a neat example of a metric unit not being the SI unit.