When we arrived they managed to give us the keys to the wrong room, so we entered someone else room. This is one of those things that should never ever happen.
We had to reprogram the keys two times in four days, not a biggie, but annoying.
The cleaning staff opened the door at 9am twice, without knocking, so I'm not sure if there was something wrong with the schedule. Told them after the first time, but it happened the day after again.
The room was really nice, the hotel is very nicely placed close to the Warschauer Strasse station which is a great hub in to the city, and a lot of nice things in the area.