We stayed at Katarina's flat for 3 nights. The location is great: Central Sodermalm within walking distance to nice restaurants, grocery stores, and galleries. We particularly like the area around the park on Nytorget.
Katarina's flat is in a quiet family-friendly building surrounding a tree-filled courtyard. The interior space is bright and open, good for relaxing or working on your laptop. The bed is big and comfy. Nice hot showers and strong coffee get you moving in the morning. Everything you need for comfortable lodging in Stockholm, with an elegant but simple style. Highly recommended.