The room is small but plenty of space for a solo traveler (and bigger than I was expecting based on the photo). I was also perfectly comfortable hanging out on the couch in the living room or making myself some tea in the kitchen, which is not always the case in shared spaces.
Location is good. There are plenty of basic conveniences (including a sizable grocery store) right around the apartment, though not likely a neighborhood you would otherwise spend much time in. It has good proximity to the sites you're going to want to see though there may be places that are closer. I walked to city hall and into the old part of town (a long walk but walkable; about 1 and 1.5-2 miles, respectively). If you're not up for the walk the subway station is extremely close and will get you anywhere you want to go.
Vendela was great in helping me find the apartment and quick to reply as I made my way to Stockholm. She had some good recommendations and was overall very personable and friendly. I would gladly stay with her again next time I'm in Stockholm.