Decent article in this month's Evo about the different premium fuels on the market. They went through a pretty in-depth dyno testing of them all. Also compared against a race-quality fuel, which is an eye-popping £3.50 a litre.
Wasn't there some comment about "freshness"? I seem to remember someone else did a test recently and (Tesco 99 not included) Optimax won by some margin..
