We stayed at Frederik and Ellen's house for over a week. The flat is amazing and we had a lot of fun. It is very clean and stylish, with a view over the canal. The location is great - quiet neighborhood, with everything you need nearby (supermarkets, cafes, buses, metro, bike rental, playground), and also walking (or bike) distance to city center and attractions.
We were with 2 kids, and the house is very child friendly - they felt at home very fast and so did we.
Frederik and Ellen helped with all our questions very fast, and we had a great time.
I highly recommend it!