36 or 40 mm? In a white metal?
But if it has to be more sporty I would also go for a (near) NOS GMT II.
or Explorer (small arrow). 
You know what? It doesn't really matter that much. Most Rolex models have a good resale value anyhow so if you make the 'wrong' choice just start over ;-) But watch out, before you know it you will own more than a pair...