ECT or not to ECT
 

For us with automatics, do you use the ECT PWR button or no? My understanding is E(lectronically) C(ontrolled) T(ransmission) takes away the line pressure requirement of shifting and just follows a trim table.

Has anyone compared performance with/without? Fuel mileage?

I like the way it holds a gear longer and kicks down sooner with ECT on, but I'm running 275/70R17 with 4.30 ratio and a lift so milage is already diminished and I need a bit more revs between shifts with the large hills in my area.