Ive tried all flavors of gas at a few local stations, by flavors I mean low, mid and high octane. BP Regular gives the most light throttle response for the newer insight and keeps vtec at bay til the going gets tough. All the other rotten crap I poured down the tank made you ride vtec and vtec kick in early.
My sidekick, he doesnt care. I use him to burn off our old gas, both for the 2 and 4 stroke stuff. Once I poured in a gallon of kerosene from a heater we were storing. No change at all in performance.