I used to go to both the NYU and upper east side studios often and had their monthly membership for years. The staff are all very friendly and there are many knowledgeable teachers. Unfortunately some teachers I like no longer teach there. There are a lot of classes offered through the day so I would just go there without checking the schedule
I had lessons with Alan and his father nearly 50 years ago and it was the best yoga, meditation and spiritual instruction I could have hoped for. Changed my life and I now practice daily utilizing Alan's excellent classes online. Have no doubt, this is the real thing!