Thanks all for your inputs. I guess we are lucky to have 93 octane here in South Jersey.
I do try to stay loyal to one brand.Usually Shell. I remember once I had to fill up our 2004 Camry 4cyl with no name gas (can't remember the name) on a road trip. The car pinged and knocked.
As soon as we got rid of that junk gas we filled up with I believe it wasChevron 93. It cleaned out the bad gas quick.

 

Yeah go for the highest octane possible, when I go to the track I always fill up with 110 octane and the car feels a lot smoother. The high compression in these cars just begs for good quality gas!

 

Gasoline and oil, everybody has an opinion and most are just hooey. Jamming in more octane does nothing except lighten your wallet, the rest just blows out the exhaust. Ideas that the car runs better, idles better, has more power using 93 or above octane is in the mind of the driver. Octane is there to control pre-ignition of the fuel and once that is obtained by a particular octane level putting more in does nothing. Octane does not add hydrocarbons or oxygen, hence an engine won't produce more power with more octane. We aren't smarter than the Lexus engineers who designed the engine and management system, use what they recommend and don't try to outsmart them.

 

I've always ran premium 91+ all day long, I've noticed through personal testing that a full tank of regular or mid-grade doesn't last as long at all, also the engine runs a lot louder and more prone to knock, not sure what its like down in the states but here in ontario I run 94 from petrol canada all the time