CopperEdge huh? Me too 2007 18" FWD SEL+!
I think it's what shoe size you drive with. My feet need size 14 shoes, but I drive with size 7's.
I'm 60% Hwy/40% City. I have been showing 20MPG +/- for most of the time I've had the car (4K miles). The number I get when taking miles/gallons at fillups is a bit lower, so I wonder about the computer in the car a bit...18 to 20by my calc's. It may be that I am not getting consistant amounts with these flaky pumps nowadays.
I drive it gently, very gently, from 0-20mph. I try to keep it under 2200 rpm. HWY speeds on I95/75/595/Sawgrass XWay run 65-80mph (travelling with traffic).
Average on the computer is 39mph all together. A/C on with these numbers. Without the AC it's a bit better.
I did put the sole to it after a fillup and reset, and sure enough the mpg avg was 12mpg - had to try it bit to see what she'd do.
Oh, and I'm in So Fla and there aren't many hills to affect things, and I do very little "stop and go" because my schedule allows me to miss peak traffic.
I reset the MPG at each fillup, and man, sometimes I'm rolling and can momentarily show 50-80mpg - then it collapses so fast it's scary!