I've measured Oregon vs California gas through the years (just posted in a different thread). What I've found is OR gas gives me consistently better MPG (at any octane) than CA due to (I believe) the ethanol content. In OR, I consistently use 87 in the PM with no problems. When I cross the border into OR then I tend to use 1/2-1 tank of ethanol-free in Ashland... I think I'm just being superstitious and want to cleanse the CA spirits from my engine.Any reason to use higher octane gas in these?