Tim, I've also owned the D200 and it is a fine camera. As for FX bodies, I was very satisfied with the D3. I had no issues shooting events and motorsports with the D3. If you have a set budget, I would go with the D3+24-70mm f/2.8 combo. It is a great combo for events. If you already have good glass, get the D3S. I upgraded to the D3S because I had the funds, not that it was necessary.
Hope this helps...JL
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