A fantastic flat, close to the city centre (incl good public transport) but super quiet. The room is large and very clean, and I was made to feel really welcome. I didn't meet Matthias unfortunately (I was out & about too much), but he was really great at communicating beforehand, and very helpful. His girlfriend and their other flat mate were there to meet me and ready with maps and advice on where to go in Vienna. Couldn't fault it, but I didn't spend that much time there as there's so much to do in Vienna!