Bonjour Yemgi,
Almost All the japanese motors running in Europe are made to use local unleaded fuel, the 95 is a bit less dryer then the 98 ron. If you check your manual or the sticker inside the fuel door says "use unleaded 95 ron fuel". I asked to my local dealer too, he replied use 95, the fuel injection program is made to run with that, according to a non modified car, now if you start to play with chip, turbo or compressor I don't know.
I can compare with bikes, giving much more power at high revs comparing to a car (except for the Honda S2000), a 1000cc engine gives you around 130cv (low end) up to 165cv (high end).
A few years ago we went with a friend with exactly the same bike (VFR800/98 with injection/same tyres/same pilot wheight), we filled up the tank with 95 on mine and 98 on his one, doing the same travel, there wasn't any difference at the end.
To compare, I filled up the tank of another bike(CBR900 without injection) with the aviation fuel AVGAZ (low leaded and around 100 ron), much more expensive than the normal car fuel, and once again I didn't notice anything.
Now if you want to race a bike very seriously, a lot of people use some special fuel, with a higher Ron indice, around 110/120, but this is for racing only, on road you would'nt be able to notice any difference, the only one you should see is a marketing one ;)
@d'taleur
vince