Unfortunately i didn't have the chance to meet Olga and Alex, because i have reached to the apartment very late at night and only my friends, with whom i was travelling met Alex. But from what i/we have found there, the beautiful apartment, the accuracy of the description on airbnb and the reviews you read are true.
The apartment is in walking distance from Gamla Stan or you can take the metro from Skanstull. There are in walking distance restaurants like Himlen and Eric's Gondolen, which i recommend if you want to have a nice view over the city, but you need to make a reservation in advance.
You can find beautiful bistro's and cafe's where you can enjoy Fika(coffee with kanelbulle(cinammonroll).
The apartment is very modern, its located in a quiet neighborhood, you have everything you need in the kitchen if you want to make breakfast or even dinner.
Everything was very smooth and we could ask Alex and Olga all our questions related to how to get to the apartment, where to go and other "stupid" tourists questions.
I warmly recommend this apartment for anybody you wants to make a city break in Stockholm and even for a longer period of time.
Bianca :)