From reading these posts I must admit I am more than happy with my 05XKR with the 4.2SC motor.

On my last 2 drives of around 650 miles each I averaged 27.5 mpg on the first one and 28.5 mpg on the second one, all on secondary roads and most of the time not exceeding the speed limit.
They certainly were not granny drives, mainly crusing with spirited moments where ever posible.
On a 3000 mile trip last year I averaged 26.5 mpg but it was a lot of freeways and at higher speeds.

Around town it goes down to 22+/- mpg or so.
I also drive in sport mode 90% of the time, use the gears and only use premium gas.

As much as I love the whine of the supercharger I do try to refrain from over doing it as it seems to cost me more in speeding tickets than gasoline but when you pull out to pass someone it just can't be helped. Iım sure you know what I mean.

Fuel consumption was not something that I considered when I bought the car but I must say I am pleased with it so far.

Allan