Notice an article in VW Driver this month reporting on some independent tests on the above three fuels run over several thousand miles in an E46 M3 CSL Here is a link to the full article: http://www.thorneymotorsport.co.uk/tuning/Fuel_Test_Results_Update.shtml In summary, Tesco 99Ron outperforms V-Power and is almost as good as the 102 RON Ultimate. Here is their conclusion: Bottom line? Use the Tesco 99 fuel where you can find it, it offers the best, most consistent performance of the fuels available and its cheaper than V Power. If you cant find a Tescos that sells it then go for Shells V Power. If youre feeling really flush, have a point to prove on a rolling road day (days where car enthusiasts compare their cars power on a dyno) or want to extract the maximum potential out of the car on a track day then the BP 102 fuel is worth a go, just bear in mind that £150 a tank would pay for a good proportion of tyres or some decent driver training.