Agree on all the economy comments.
Don't buy this type of car if you are worried about fuel uasge. To be frank, and please don't take offense, its a silly question. It has a 3.5 litre V6 petrol, it will never be a frugal car, no matter how you drive it.
It'll drive you potty watching the fuel gauge all the time. Not only that you won't enjoy it.
What's the point in have a car like this if you can't open the taps when you want.
Accept it for what it is and then you will fall in love every morning when you hear that V6 bark into life
I know I do.
Bradders.