As many of the other reviews will tell you, Ester is a great host. She is very welcoming and is willing to accommodate if anything comes up. Even though she lives a very busy life, she is always willing to strike up a conversation and offer any assistance if needed.
As for the room itself, everything was as advertised. There's a separate AC unit in the room which is a big plus if you're staying in the summer.
Roosevelt Island is also a great place to stay. The area has a great vibe and feels very safe. The only thing to keep in mind is that there is only one subway line that serves Roosevelt Island, and during the weekends, there are sometimes closures in certain directions. But as long as you are aware of the other transportation methods and plan ahead, you should be fine.
Overall, I don't think there is a better Airbnb to stay at when visiting NYC, especially with this unbeatable price!