It's been a more than a year since I saw Dor. And, I remember having read somewhere that this was a copy of a Malayalam movie that was even better.
Now that I am done with the disclaimers, I must say that I absolutely recommend this movie. The theme is pretty rivetting (though the treatment may seem a little slow in places), and the acting by everyone is very good by everyone. It is the best I have seen of these three actors - Ayesha Takia as the Rajasthani village bride/wife, Gul Panag as a determined woman trying to save her husband and Shreyas Talpade as the bahurupia.
Overall - Watch this one if you haven't yet. Highly recommended.