I had a lovely time staying at Thor's place for my month-long stop in Berlin. A pleasure having him as a flatmate; Thor was friendly, considerate, and accommodating.
His place is in trendy Kreuzberg, sprawling with hip bars, restaurants, vintage shops, food stores, and public parks. I found it highly accessible to places I frequented: gyms, clubs, and cafes.
Overall, I'd recommend Thor and his flat, especially if it's your first time in Berlin. You'll find his wealth of insider knowledge pretty handy! :)