I would love to live in NYC (having lived in CA my whole life), but I would still choose UCLA any day over NYU. Not only does UCLA have what I consider to be a great curriculum, the many thousands of dollars you would save will go a long way in the future.
to play devil's advocate, i dont think there is that much of a difference in rep between the two. if it were ucsf v. nyu, thats a different story. i dont think it would be crazy to pick nyu if you really wanted to be in nyc. compare matchlists.
i dont think there is a question. i currently go to NYU as a graduate student and went to ucla for undergrad...so i cant speak about med school....but overall UCLA is much better. Med school at UCLA is like leaps and bounds better than NYU supposedly too. youll also like westwood (which is so much better than greenwich). if you want to be in NYC...i guess thats the only big advantage that NYU has. LA is a good city too. ha.