The main reason for asking is we are about to go up to Scotland touring in the car. There does seem to be a reasonable amount of petrol stations with E5, from what I'm reading, if I'm stuck , the odd tank, or half tank of E10 will be ok.
Previous to the switch to mainly E10 I used standard unleaded, which was E5. Since now only running on premium, Vpower etc I have noticed a gain in performance. Also MPG seems to have improved .