Had an easy 12 night stay at Sarah's. The apartment is bright and spacious (especially for New York). If you're a light sleeper it can be a bit noisy from the traffic/subway and the boiler is quite loud.
I wouldn't say it's in the coolest part of Williamsburg but I felt safe walking home alone at night and it is so conveniently close to the subway which makes it very easy to get around.
I didn't see Sarah much but she was always friendly and helpful.