It makes a huge difference because it stops you from using the engine inefficiently. They don't put it that MPG on the sticker because if a car drove like that normally people would not buy it. You step on the gas a little and you only get a little bit of acceleration. But you learn to live with it and you get as good a MPG as the Prius at much lower price. You can stamp on the gas and it overrides the eco mode.

One issue is that the air conditioner shuts off when the engine isn't charging, but I compensate for that by setting the temperature lower than normal so it fluctuates where I want it to be.