Hi fellah
they're just teasing but there's truth behind their cheek. this subject comes up quite regularly and there are numerous threads around, but it really depends on a lot of factors - whether your notching up mostly A road miles, or motorway or town/city driving or a combination, how heavy you are on the gas pedal and which supra i.e.: standard TT (not that there are many of those around ) BPU, Hybrid tubbies, single tubby, N/A etc.
An NA will give you the most miles but that in itself can vary between around 280 for heavy foot/heavy traffic to around 360 for mostly long haul.
Overall though fellah, if your concerned about petrol consumption, bear in mind they are all 3 litre engines and therefore thirsty beasts!!! Be prepared to dig deep for fuel but the rewards are AWESOME!!!
happy hunting, don't let this cheeky lot get to you, its standard on the forum so you'll have to harden yourself All good natured stuff
lolx
Linda