Choosing a thermostat temp. Why so many choices?

I want to change the thermostat on my '97 Taurus and there are three different temp thermostats to choose from. What are the advantages and disadvantages of each?



I don't remember the exact temperatures but you get the idea. The factory temp is correct.



180潞C Factory

165潞C

135潞C
Choosing a thermostat temp. Why so many choices?
stick with the factory its the best



if you choose any other one your car is going to run rich for the whole time you are driving and you will be using more fuel for no reason
Choosing a thermostat temp. Why so many choices?
Stick with the 180, the others are for those people who have reasons, either real or imagined, to deviate. Also, the t-stat manufacturers list all that fit, not just what is called for.