If you're concerned about the break-in period on the car, I certainly wouldn't call autocross "taking it easy." That said, I know people who have driven cars right off the lot, slapped on Hoosiers, and started throwing the car around an autocross course.
There's nothing wrong with a new car when it comes to autocross, but as far as your break-in-period, maybe you should go on a couple road trips first.
Chris DeLay
1989 ST Civic Si (a.k.a. "The Polish Flyer")
2000 DS Integra Type R (resting)
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