3264x2448 or 3264x2176

I am going to New York City this week and I am going to be taking a lot of photographs. My camera has two options for image size: 4:3 ratio 3264x2448 pixels, or 3:2 ratio 3264x2176 pixels. Which one do you think I should primarily use? I am aware that the 3:2 ratio will come out with no cropping on a 4"x6" print, but with the 4:3, I have the ability to shoot more area.

I'd go for the larger size so you have more cropping options later. It shouldn't be a huge difference on how many shots you can get on a memory card - plus, memory is cheap!