I use PLUS from United servos. It's a 95 RON E10, (10% ethanol blend).
I've been using it for ever in all my cars with great results even from the Renault which runs a similar comp ratio as the focus 10.3 : 1
Sure ethanol isn't as 'energy dense' and in theory a tiny drop off of performance compared to straight 95 petrol - about 2% I believe. I doubt anyone could ever tell the difference.
So at more than 4c per litre cheaper than normal 91 unleaded I'll stay with PLUS
More info here if interested
http://www.unitedpetroleum.com.au/news.html