ordinary supermarket unleaded is fine. it's 95.
super might give better mpg
I use esso Synergy Supreme+
because it doesn't (usually) have ethanol in it, but then my car is not used every day, or even every week.
ethanol in fuel is generally a good idea as its a good octane booster, and nominally 'greener'
however, if left, it can absorb water from the air (hygroscopic ), the fuel degrades, and may even separate with a layer of water at the bottom of the tank
The 1.0 ecoboost is quoted as being a very high performance engine for its size and my personal opinion is therefore that 97 RON petrol or better should be used. I've started trialling Tesco Momentum 99 RON at £1.34.9 a litre despite always in the past avoiding supermarket stuff. Shell V power which Honest John recommends is 10p more per litre. I have resorted occasionally to alternating 95 with 97/9 RON. The "experts" say its a waste of time doing it that way so as they adage goes you pays your money and makes your choice!