I spent about one week in Berlin with my wife, on a mix of business and leisure. Our stay at the Adina was overall an excellent experience, with spacious rooms, very helpful staff, and a lively and cozy atmosphere (e.g. fireplace in the lobby). All major attractions are a comfortable walk away, and the hotel's location, although so central, is still very quiet. A supermarket and other stores are literally just around the corner.
This said, we were a little disappointed that our parking space in the hotel's underground garage, booked in advance, was not available during the first two days of our stay. Apparently cars which are not entitled to enter make their way in, and since the garage is very small, it is almost impossible to "escape" once you are inside. Adina staff, do something about this!! We switched to street parking with a pass provided by the hotel, and were pleased to find that it was not difficult to find a space in the streets surrounding the hotel. Overall, a small nuisance which did not change our overall very positive impression.