I have found that using premium 95 in my 2013 Presara (GSV50R) gives better fuel consumption than 91/92 octane. I generally average 7.5l / 100km. In my previous 2007 Camry Sportivo I regularly averaged 6.5 l/100km even when fully loaded using 95 octane.
I usually get 6.5 to 7.5 litres per 100k using unleaded 95. I was using premium 98 but found I was having starting problems when cold, returned to 95 and all good. I drive a 2007 Camry Sportivo 2.4 litre