would it be fair to say using the more expensive unleaded fuel in my car is better ive found i seem to get more mpg and maybe a slighter smoother running

It's said that it is all in peoples minds but, chemically it is better as a higher octane reduces detonation before the piston has reached it's optimum stroke.

Octane does matter but, if you don't have a high compression racing engine, I doubt the price is justifiable

Daz

I use Momentum99 or V-Power but thats strictly because I Have a remapped engine and it runs better on that than the other lower octane fuels :)

+1 and +1 ;)