Never stay at a Hilton. You are paying for the name.
There are many smaller, older hotels on the upper east side that are very reasonable.
I had no choice as the room was booked by my company because all the meetings were inside the hotel.
As far as Hilton's go, the NYC Midtown Hilton is much much more expensive than any Hilton I have ever stayed in. The midtown location is what they are gouging you for. But it is all the misc. taxes added to the bill that really run it up. They really stick it to the visitor. Even the cheaper hotels have to add these in by law. I always feel ripped off when I travel to NYC. I avoid it as much as possible.