First thing first, this hotel is not located near the metro station Rathaus, although that's that what I get from google map search. It's in fact in between the station Westbahnhof and Burggasse-Stadthalle. The entrance of the apartment is at Kenyongasse 17, but check-in is on the other side of the building along the Neubaugürtel.
Overall of my stay is great. I rented the apartment for 5 nights. The bedroom is nice with a small pack of gummy bear candy on the pillow, which is cute. However, it smells a bit like food when I walked in, I suspect it's from the previous guest? Apart from that furniture-wise, bathroom and bedroom are all quite clean.
The location is pretty convenient too, with just 5 mins to the nearest metro station. You can also walk to the city centre in 20 mins. Hotel has free sauna and a small room with some work out equipment. p.s., you walk throuhg the sauna place to the gym room, which is a bit weird.
Overall, the hotel is pretty good.