Enthanol blended fuels have a higher RON, in fact it's so difficult to ignite pure ethanol in colder climates they have to blend with petrol just so they can use it. Probably why the Peugeot likes it, fancy timing and valve technology.

If your car is set up for ethanol (correct fuel lines and high compression/advance) then you can make good power from it. Just watch out for extended periods of inactivity as the ethanol soaks up moisture like a sponge.