i've found that mid-thermostat plus low fan speed cools the cabin faster under normal situations. thats probably because the air from the fan has more time to pass over the cooling fins of the evaporator, instead of just blasting high speed air.

here in the phils i run my a/c at mid-cool, fan setting 1 or 2. oks naman. paired with super black tints... ok na ok. the compressor cycles at half the number of times than say, at high cool.

gained fuel mileage is small, but over long distances it can pile up.