I stayed here for a multi-month stay, and it's well-suited for that. It's right on the M2 line to Alexanderplatz, which means getting anywhere in Berlin in relatively quick. The flat itself is spacious, with lots of light from a south-facing window. It's two courtyards deep, so there's no street noise, and the neighbors are quiet and friendly. Armin is a great host – he was there to greet me when I arrived and explain everything, and always responsive if I had any questions or issues (which were very minor in nature).