I booked this apartement for my parents (60+) who came over to Québec for a visit. Although the apartment was not the one shown on the pictures, my parents enjoyed their stay in the lovely rooms (which are actually close enough to the photos). The contact with Dimitri was always very pleasant and he's really, really fast in leaving a reply. Thanks for that!
There are two buslines (1 & 80) but they're operating only once or twice per hour, so mostly walking will do faster. If you're planning to explore Québec by foot, this apartement in Saint Saveur is perfectly situated in a quiet part of Québec - and already on your way into Vieux-Québec, you will enjoy some nice corners of Québec (Park Victoria, Rue St Joseph...).
So all in all: If you're looking for an uncomplicated accomodation, I'd strongly recommend Dimitri's apartement.