Just read this article from the Times, albeit a year old, and was wondering who uses which fuel type and have you seen any differences or have any preferences?
https://www.thetimes.co.uk/money-mentor/income-budgeting/cost-of-living-crisis/is-e5-petrol-more-economical-than-e10#:~:text=But E5 is more expensive,therefore get you 121 miles.