It was a great experience to be hosted by Guido & Stephanie at their place. The apartment is very clean, full of amenities and very well connected. Spar, Billa, medical store, tram & underground metro stations are just a couple of minutes walk away. Stephanplatz and Naschmarket are about 10-15 minutes by underground metro. The apartment is in a secure & quite residence on the 3rd floor. Both Guido & Stephanie are extremely helpful and made sure that even the smallest of my requests were honored. I came to Vienna on a business trip and stayed at the apartment for over 40 nights. The first time Stephanie visited the apartment for a minor issue I had with the internet, she was very kind to bring a box of chocolates for me. It was very thoughtful of her and the gesture in itself was priceless.
I would totally recommend all the apartments hosted by Guido. It's easy to find an apartment but it's hard to find good people who would give you all the space that you want and still make you feel at home.