We had a wonderful stay in Vienna, Dan was very fast in his communication, so any questions where answered within 24h (more like 2h :D). The appartment is clean and spacious enough. Good nice and clean bathroom.
But the biggest plus is the location, just corssing the bridge and you are in the middle of old Vienna. a 5min walk to st stephans cathedral. really really nice.
Conclusion we had an very good stay in Vienna and will be returning.