I am getting about 1-1.5 mpg better using power mode than normal mode. This seems to be about two mpg better when using the a/c. The car is also so responsive in power mode. Why is this? My next test is to see if power mode will give me better mpg while cruising the highway with the cruise set at 75mph. Any thoughts on why power mode is getting my better mpgs? Maybe I should always use power mode!