Nestor Marte, Ultimate Gym NYC?
I believe Nestor trained and lived in Thailand for about 8 yrs or so before opening the gym. He's been teaching for about 10 yrs or so as far as I know. See what kind of fight records his fighters have. Some of his guys must have some am or pro fights under their belts. That will give you some idea of his ability to train others.
All in all, looks legit to me. Expensive but it is NYC............... right?