Stine's apartment is located really in the heart of Copenhagen and was a great point to discover the city. She herself was a very helpful and flexible host who always responded quickly to messages.
It is true that the area gets a bit noisy at night (mainly during weekends I would guess) but if you bring earplugs like she suggests, there's no problem.
Would recommend to a couple that is travelling lightly (big suitcases might be difficult to get up the stairs) and who are planning to be out and about during their stay (flat is decorated in a minimalistic way which is totally perfect if you're not looking forward to stay in much during your stay).