It's hard to fault Jolanta's place. I stayed for a month, and it's well appointed, mostly quiet, and very close to several u- and s-bahn stations. It's perfect for travelling professionals, or to use as a base while searching for longer-term accomodation. The only (potential) downside is that the area is fairly residential / shopping-focussed, and there's not a lot nearby in the way of small bars, cafes, etc, especially for international travellers!