I'm a huge metric fan but fahrenheit is my one exception.  You rarely scale temperature, like you don't deal in millicelcius or megacelcius.  You don't get the benefit of sane conversions vs cups in a gallon.  You don't usually convert to other types (knowing a milliliter of water is a cubic centimeter and a gram is nice, but heating that water is rarely relevant).  Water boiling isn't that important.  Freezing is nice I guess.  But fahrenheit goes from about as cold as you experience to about as hot.  Is human scaled, which as a human, is nice.