Great place to stay especially if you need a room for more than two people. The apartment was spacious and clean. It was with in walking distance to the station, some of Berlin's sights, and there were plenty of restaurants and shops in the area. There is also a small restaurant in the main area.
Make sure you arrive to check in ( or let them know ahead of time) before 8 PM, because after that the main lobby is closed and locked. Durning the rest of your stay this will not matter as you key will let you in the other entrance.