for me i dnt really care much bout gas savings... not that im filthy rich either.. but i hav my reasons.. what i do in my starex is to keep the fan at number 1, and the termostat at the coldest level. in this way i feel it will be more effective, and use less energy from the engine because the compressor doesnt work for longer period of time trying to cool the inside of the car..than when you hav it at a lower setting.. it will turn off for longer time and then be on for a longer time too.. so i dnt really ther is dat much difference...
i have magazine where they did a survey on the savings of using the aircon of a car and not using it.. the savings was insignificant... when you dnt use your aircon... well thats just my 2 cents..