Who wore Zac Posen better?

Both Nicole Richie and Cynthia Nixon have stepped out in the lovely blue dress from Zac Posen's spring 2008 ready-to-wear collection.
Cynthia Nixon was spotted wearing this floor lenght gown on the set of "Sex and the city:the movie".
Miss Richie wore the same dress to the the Montblanc charity cocktail, on March 6, 2010.
I adore this dress on Nicole as I think she looks so elegant in royal blue.
What do you think?

poll by twiigs.com