I've stayed at this hotel twice. The advantage is that it is located on a quiet street, but at the same time three minutes from the Radmansgatan metro station. And this is the center of the city.
Last year I moved into the hotel opposite - Rex Hotell. As it turned out, this hotel also belongs to Hellsten, judging by the labels on all items (tableware, textiles). It's cheaper at Rex, I think because of the more modest breakfast. For 4 nights at Rex, you save about 100€ compared to Hellsten.
Otherwise, they are similar.