Location: Top, in the middle you the heart of Berlin. All shopping malls and touristic attractions are reachable by walking or underground.
SPA: Very good, very clean spa. Pool is a little bit small, but nice.
GYM: State of the art, very clean,
Rooms: Diamond member are able to get access to executive area and lounge. For hotel is always booked as gold member it is difficult to get upgrade. Room are very clean and staffed.
Aircondition/Heater: It was winter and aircondition/heater did NOT work. No other available room, so it was very cold in the room. Room are staffed for a 4 star hotel. It is not possible to put own soft drinks etc. in refrigerator for it is a "payable version" fully staffed with expensive things. If you take something out and put instead own drink in, you have to pay for the bottle you take out.
Staff: Sometimes nice, sometimes rude.