I have been using Ron 97 all the while in my rusty car. Then when price went up, i started to use 95. Just need to calibrate the carbs and i'm good to go. Its already 3 years right? No problem so far. But i hate Petronas. 2 times i used this fuel for 1 week, it killed my fuel pump and clogged my fuel filter. Basically the fuel is too clean and abrasive. Old cars do not agree with it. The same thing happened again with Shell. I tried it because of Bonuslink. But have always been Mobil or Esso for me.