If cost is not a consideration, the NYU all the way. Several things I don't know if people have fully noted yet:
1) NYU has more reach in CA than Duke. It won't be "easy" from either school, but NYU is a better shot as confirmed by many practicing litigators.
2) Assuming you miss CA, which is a sizable chance that you should account for, the more prestigious firms will dig deeper by a small margin into NYU. You are overestimating the power of your location and comfort in your GPA, and so you should act on the assumption that you could make the same class rank (i.e. median) at both. For large firms in NYC, the stronger alumni network and connections will place you better at median.
3) You already have a Duke alumni network as a UG. Adding an NYU law one will act as a supplement. I've been told its always preferable when dealing with comparably prestigious choices to establish an additional network, since your Duke UG ties won't just disappear when you go to law school. Broaden your base.
Good luck with your decision, you can't really go wrong either way but I'd definitely take NYU.
(Rankings, Profiles, Tuition, Student Life, . . . )