Location, location, location! Steps away from the Albertina, you can see it out the window, everywhere within the Ring is walkable. You'll be spoiled for choice about which bakery to choose to get your fresh bread / pastries / rolls in the morning - there are several within minutes walk.
Yes, there is construction on the street (a major project creating a new underground car park) but with the window closed, you won't hear anything - it is floors below you. The a/c is fabulous. We were there in an early warm spell and slept comfortably.
With two decent size double bedrooms and two bathrooms, as well as a separate w/c, there's no fighting over who showers first.
Do try Rheintaler Gasthaus on the Glucksgasse (you can see it from the apartment). This is OLD VIENNA proper, one of the few authentic restaurants that are frequented by locals. (Monday to Friday only, cash.)
Self check-in and out could not have been easier. Highly recommend.