There is no need for a higher octane gas unless you are experiencing pre-detonation. Save your money and buy the 86 octane. All major chains have basically the exact same gas save octane ratings. I personally like Chevron gas because of the techron additive, which helps cleans deposits off your valves and the like. However all large chains have their own types of additives. The best place to gas up is any station that has plenty of business, they have fresher gas. Fresher gas means less time for water and sediment to seep into the gas. Never fuel up if you see a fuel tanker at the station. When they make delivery of the fuel it stirs up any contaminants and increases the chance of you pumping them into your car.
I buy cheap gas at Murphy, USA right next to Super Wal-Mart. They have good prices on cartons of cigarettes, too, and sometimes they give away free lighters.
--- Legend, oh legend, the third wheel legend...always in the way.