Silvia is a perfect host. She was very welcoming, replied to the messages promptly and let us check in 3 hours earlier, which we appreciated very much. She also called us a cab (a driver she knew) to JFK when we were leaving, which I think helped us save about $20 (compared to the yellow cab fare). The appartment itself is very clean and offers everything one might need. However, it's not really sound-proof: you can hear people walking upstairs. And the air conditioner is a little loud. It didn't bother us at all, but if you are a light-sleeper this could be an issue, I guess.
The location is very convenient, really close to the subway (5-7 mins walk). The neighbourhood seems quiet and safe.
The overall experience was very nice and I would definitely recommend Silvia's place.