I use the slightly more expensive fuel at VIR (93 octane or whatever the lowest is). Mostly because it's convenient. I know exactly how many gallons I want and the pump counts it out for me. I don't own enough fuel jugs to get through a weekend and the cost of having to drive the tow vehicle around to get more fuel pretty much offsets the cost of track fuel. Of course that will all change when I finally get my ECU installed and tuned.
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