I'm really very partial to dual head cards that have dual DVI output, rather than the split VGA / DVI or dual VGA. I tried running 2 identical Princeton 19" monitors -> one on VGA, the other on DVI and it drove me NUTS!!! I could NEVER get them to "look" the same. One looked so different, and I mean bad diferent, I even returned it and got another one (costco), but it was the same deal.
I upgraded to a dual DVI video card, and Voila! Perfection.