Btw, I have been doing quite a bit of research myself regarding the petrol suitable for my 318is.
Tried Caltex platinum, gold, Esso 98, Shell 98, Vpower. Also tried these 3 brands in Malaysia.
Guess what?
I achieve the best mileage when I mix Esso 98 with Shell 98 (1/3 Esso, 2/3 Shell). I achieve almost 11.7km/L. For Esso alone, its 11.2km/L
Vpower gave me the worst mileage, just 10-10.2km/L. Msia even worse, 9.2-9.5KM/L.
Caltex platinum is around 11km/L. Gold also the same. Pumping gold in Malaysia gave me 10.3km/L.
Current on msia Esso F1. Looking very good. I reckon it should be around 11km/L as well.
I think I can safely say that Esso petrol gives me the best mileage. Power wise, not much of a difference. All around the same.