Our stay was generally very good. The staff were friendly and helpful. The room was clean and matches the photos quite well. The location was convenient for us, as we were a short (<5 minute) walk from the train station (S-Bahn).
We had a really great time in Berlin, and this hotel was definitely a part of that. It was comfortable and clean, and we enjoyed our time there. The room was very spacious.
I would note that this does not meet many peoples' expectations of a traditional hotel. It is more like a hostel that had been converted into a hotel. There is daily room cleaning, which is good.
The surrounding area is quite dimly lit at night which can be uncomfortable for some people walking back (alone) at night.
This location is excellent if you intend on visiting Christmas markets (as we did), since it is close to Spandau, Zoologischer Garten, Alexanderplatz and several other Christmas markets.