Ales's apartment is very close to to central part of Vienna. It's easy to reach by metro/tram/bike. All rooms we had access to were very clean and well kept, we had a great time at this place and in Vienna too. I also thought it was very cool that the first thing we saw when we exited the metro station close by was the heating plant building redesigned by Hundertwasser.
I would absolutely recommend staying at Ales's.