I stayed here earlier this month for an extended trip to Berlin and was very happy with hotel and the cost of the room.
The room was basic but clean, the location is excellent - plenty of places to eat, and lost of really nice bars, in a short walking distance. The hotel is very close to the U-Bahn so getting around Berlin is very easy.
The staff were extremely friendly, I did not need their help as it was not my first time in Berlin but they struck me as people who would be more than willing to help if needed.
Overall, if you are just looking for a bed in a clean place that has an excellent location stay here. This hotel will be top of my list the next time I visit Berlin.
Just a small, constructive suggestion for the owner: do not disturb signs would be very useful for the rooms.