I can't say enough good things about Mona! She was so helpful and kind when I came into Oslo after a long hiking trip.
The studio is small, but comfortable, and right in the middle of a great neighborhood. The spots that aren't right there are totally walkable from the apartment, and it would be great for one or two people that are looking for a small quiet home base to explore the city.
If I come back to Oslo, I would definitely stay here again. Definitely recommend.