I kept mine below 4 grand for the first 500, and am upping to 5 grand for the next 200. Still haven't full-throttled the car, and it's not like I'm living above 4 grand now, I just give myself the extra revs for getting on the highway easier
I will say this though, simply riding it through to 5000, the car REALLY started to come into its own. Noticeable change in power that makes me very impatient to wring it out to 7000.