The knock sensor can compensate for 95 RON. 98 is ideal, but plenty use the lower octane with no real issues.
Where I live, 93 (M+R)/2 isn't even available (98 RON). The nearest station that has it is a 1.5 hour round trip.
I've been running 91 (95 RON) for a few months and notice no significant difference. A bit less power, but that may be in my head.