mid 30s from the 4.4 is to be expected, the 3.6 usually hovers around 25mpg..
I wish .
Best we see is low 30s on a long run wearing slippers
But normal is around high 20s from guessing and the lie O meter.
The 405 gives better and would agree those figures are attainable.
But We don't care, you want it, and can afford it why not spend hard earned beer tokens on stuff that makes you happy.
J