Interesting. BMW suggest that the car I have ordered runs best on Shell V-Power. I’m considering using that for the first 1,200 miles run in period, then using Tesco Momentum Super Unleaded, with every 4th refuel being Shell V-Power. However, the supplying BMW dealer tells me that they use standard unleaded on all their cars, including full fat M cars, but I had read some user reviews on line that they get better performance and mpg from using the more premium fuel, which helps offset the additional cost. That seems to chime with your experience. @kezo I always value your views on these things.
The bioethanol content regulations “was” based on upto % and once upon a time in the not so distance past, you could fill up with E10 95 RON and feel confident you were getting E5 97/99 RON, if you new the fuel station got its fuel from 2 of the UKs ethanol plants (hence one reason for me using Esso), however Starmer fecked that up with the US trade deal and the agreement to imort US stuff.
Plenty of youtube video’s and info out there