The apartment was lovely and just as advertised. It was clean, well appointed, and the location couldn't have been better - right in heart of the city center (Indre By) and walking distance to the train station, great shopping (it's on the Stroget), cafes, restaurants, and most of the tourist attractions. It was a self check-in/check-out so that made everything really easy -- no having to arrange to meet anyone to get access to the apartment.
Den was really responsive. The apartment had a washer/dryer in the unit which was very convenient. During our stay, the dryer was broken but Den arranged to have it fixed as soon as possible so we were able to use the fully functioning machine in the latter part of our time there. Since we had a longer stay than usual, he offered to have housekeeping come mid-stay to freshen things up for no extra charge. It might also have been due to the fact that the dryer was broken but still it was nice of him to offer that.
Overall, I would highly recommend this apartment. It was by far the best place we've rented through AirBnB.