I also have a Torch Red Mustang, and I used to live by NYC. And all my rock chips have come from NY as well, so I feel for ya.
I ordered touch up paint from: http://paintscratch.com
It takes a bit of patience to get the finished product to be as smooth to the touch as the factory paint(I got the clearcoat also), but the color matches exactly in my opinion. It works better on smaller scratches and nicks. I had some chips down to the black, and they were more difficult to fill in all the way. I think with more applications and patience, I could get those looking better too. This system allows you to remove the touch up paint without affecting the factory paint at all. Good luck!