Toknia 100mm 2.8 Macro vs Nikon 105mm 2.8 Micro

I am interested in purchasing a Macro (micro) lens for my D90. I think I have it narrowed down to the Tokina 100mm and the Nikon 105mm. I would think the Nikon would be the obvious choice, but about a $400 difference. Can anyone tell me if the Tokina is a good lens? It gets very good reviews. I have read that the comperable Tameron 90mm 2.8 Macro has had problems in the D90. Nikon lens has VR which I do not belive the Tokina has so that is an advantage I am sure.

Plan is to use the lens for both Macro work and Portraits as well. I am not a professional, just an amature getting better as I practice and want to get better in these areas with a specific lens.

Thank you for any feedback