My car requires at least 91 octane unleaded, and I've been burning top-tier gas in it since Day One (Shell 93 octane "V-Power," FWIW)... I'll only put top-tier gas in Fiona, too, and never anything more than 10% ethanol (and then, only because we can't get uncut gasoline where I live). This new rule about the 4-gallon-minimum sale is a trifle annoying, too, to say the least. I don't buy anything from gas stations that sell 15% gasohol.