I had a good stay at Jesper's. The flat is located on the top floor, and it has a great view over the river. There are two entrances to the building, which I thought was great. But I had no key to the river entrance. Put into consideration that there is no elevator, and the stairs might be steep & narrow. There is a mini market 2 minutes away from the flat (you have to google it). Bunch of places to eat & have a drink are also within 5 minutes away. The city center is about 15 minutes walk, and to the main attraction (the Nyhavn) it's about 20-30 minutes walk depending on how fast you walk.
The flat felt like being home. It had everything you could think of, so I didn't have to purchase all that one might need to cook.
Overall I had a great stay and I would recommend staying at Jesper's if you are a group of 2-3 people, and looking to stay for an extended period.