My personal advice is avoid using neg hits until you know the person and you know she'll take it in good humour.
In an ideal situation, you bust on her, she'll laugh and hit you flirtatiously etc, but in reality, it depends on the person and her mood. Contrary to what a lot of "master seducers" teach, not all women take well to this approach. Some find it insulting and others might just think you have an attitude problem.
In all likelihood, these "stuck up broads" you mentioned will not take well to someone coming upto them and digging at them, no matter how playfully you do it. In a place like New York, I expect most people are caught up in their own business and have little patience for chit chat, so you're probably best saving your DJing in general for a more relaxed environment.
I find neg hits work great with my friends, but after upsetting and offending a number of women, I avoid them until I know they'll take it in good humour.
