Petronas stations in Putrajaya are pioneer in selling RON95 petrol before officially introduce to whole Malaysia in upcoming September. I pump a full tank to my bike after visiting waterski competition in Putrajaya. My fuel tank is almost empty and I can judge how good the fresh RON95 fuel is. I use RON97 petrol all time, although RON92 is applicable to my bike. Notice that RON95 give more vibration to my bike compare with RON97. I can feel it from the handle shaking after cruising above 90km/h. No improvement on acceleration. Fuel economy wise, no big different, level at 50km/l (but it save me Rm0.05 compare with Rm1.80 of current RON97)
Plenty info says that RON is not going to give more power boost. RON is just basically an indicator on how it reacts to engine knocking. High performance engine like race car usually demand higher RON fuel such as RON98, which is our Shell V-Power. Normal car engine usually are rated as RON95. Hence using RON97 is a waste since engine will not gain any improvement beside you pay for higher fuel price of RON97. I highly doubt about this. Once in a blue moon I use to pump V-Power (RON98) because it can help my bike to maintain top speed much easier. Not to forget about smooth acceleration of it. RON92 is cheaper but it just too many vibration from engine and no fuel economy advantage. It is quite reluctant in fast acceleration, thus I end up to throttle more for high speed.
Conclusion, pick the fuel suit your driving style. If I am going to maintain average speed, lowest RON is OK for me. Since I am a speed racer who travel 150km per day, high speed is only thing I look for, so RON97 still my favor. RON98 when I feel the need for speed.