The apartment is really well furnished and also many small details make you feel warmly welcomed (such as coffe, make up remover, small blackboard with welcoming message, lonely planet guide..)
The position is also awesome, just next to the M2 stop (that takes you in a few stops to Alexanderplatz) and in one of the nicest neighbourhoods in Berlin. We only stayed one night but I would have stayed more, the kitchen was also really well furnished, if you plan to have meals at home.