The location is very convenient. A lot of landmarks and places of interest are within 15 minutes walk. If walking is not your thing, a subway station is a couple of blocks away.
The apartment itself is spacious. The rooms are far from each other, so you and your friends can get your own private place.
The soundproofing could be better though: we could hear every word that people in the next apartment were saying. Also, there's something wrong with the plumbing. The heaters were randomly making loud gurgles waking us up in the middle of the night.
All in all, it was good. If not for the noise and some trash left by the previous guests, it would be a 5-star stay.