Shelley's place is in an absolutely perfect location in Vienna - everywhere you look, there's a place to eat or shop, and you're steps away from a major square and St. Stephen's Cathedral, and also steps away from a major pedestrian-friendly stretch that takes you past many restaurants and shops on the way to the Opera House and other attractions.
Shelley is a great host - warm and friendly, with two furry co-hosts who do their best to welcome you as well! I was feeling under the weather during my visit, so I spent both evenings to myself, but did have a great chat about our travel experiences during the morning before I left.
The only issue, which is certainly not Shelley's fault, is that I was there during a prolonged heat wave and it was quite warm in the bedroom during the day. Just bring some water to keep you well-hydrated and you're good.