We spent five nights at Valentin's place. Although we didn't meet him in person, the communication was easy, fast and Valentin was a very welcoming host! The loft is nicely equipped and the art is great. The beds were comfortable and bedsheets & towels were at reach. The shower was wonderful, however the toilet-flush didn't have a strong waterflow, which made flushing hard and was difficult with four people who have to use the bathroom ... The doorkeys can be a little difficult to handle at first, but after the first day we figured everything out.
The area, Williamsburg, is hip and beautiful - right around the corner there are many great bars and restaurants that aren't so expensive. Many local people were hanging out in Williamsburg, which made the experience much nicer than being in touristic areas such as Manhattan. We stayed out late at night and never felt insecure. The metro-station is nearby and even has an elevator for your luggage ;)
We would definitely love to come again!