[cyclone1410]

I did similar research around 18 months ago and tried both the Shell and BP versions. After two tanks of the BP E10 I went back to 98 Ultimate for awhile as the negative performance and fuel consumption effect was noticeable to me though not my better half - she drives like a nanna and never refuels.

I tried the Shell version and it was in my view better than the BP E10 though subjectively still behind 98 octane fuel. Consumption was also affected though not more than 0.3 l/100km with the Shell version. I still stick to 98 RON fuel though as we don't do may km's per year.

Hope this helps.