One thing to think about, and it's what keeps me away from road courses more than I would like, it is MUCH more expensive to go a road course than it is to go to a 1/4 mile strip. Wear and tear is up, tires are up, brakes/fluid is up, risk is up, everything is up up up...
I know you weren't explicitly saying this was your path, but just in case it's banging around in the back of your head...
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