I was staying in the apartment for a month. It's in a great location, it's very easy to get to anywhere in the city from Union Square.
Unfortunately, it's not very well equipped. You need to bring your own towels, there's basically nothing in the kitchenette to have proper use of it. The bed is quite old and is making a lot of noise.
There was also no hot shower for 5 days at beginning of my stay and I was not warned about that during check in.