You dont get fuel efficiency WHILE setting fast 0-100 times.
That being said I drive my 30d hard, and I still get 8l per 100km compared to the manufacturers claim of 6l per 100km.
(And the 14 & 15 l per 100km I used to get in my last two petrol 4WDs)
And, man, you should have optioned the cargo net. I have it and it is fantastic for keeping loose loads where they belong.