The hosts were kind and helpful, the apartment was clean and nice, and the location couldn't be any better, super central at the old city with walking distance to both Normalm and Sodermalm.
BUT, the master bedroom is above a noisy restobar and a main street, which is active until late thursday through sunday (on monday the room was quiet), and - as there's skylight 20 hours a day during summer - it was impossible to sleep there as the room was flooded with light. If you're not sensitive to these two issues - then the apartment is a great choice. For us it was a disaster.
The other room (with 2 single beds) was fine - quiet and dark enough.