This place was really great and I highly recommend staying here. There were three of us and it was more than comfortable and they provided everything we could have needed. Their description is accurate: it is clear that they do live in this apartment but it did not deter from our positive experience. Check in was very easy and Sebastian was there to greet us and walk us through everything in his place. I really liked that the toilet was separate from the bathroom - it made getting three people ready much easier.
Location is great! It is a 20-30 minute walk to the historic centre, a 5 minute walk to the nearest subway station (and the subway station in Vienna is EXCELLENT!), and there is a tram stop right in front of their place. There were many local eateries but most were not open very late.
As mentioned early, the place is clearly livable but clean. The only thing that did not seem to be disclosed was that they may have a pet (There were some pictures on the wall.) My brother is mildly allergic to cats and had trouble sleeping on the pullout sofa. Other than that, great stay!