Great location, right across the street from the Las Heras subway station on the H line. The Buenos Aires "Subte" system is great and simple, and so from the H line, with a little planning, you can get to all the best sites in Bs As. It's also only a short walk to some great sites in Recoleta, like the Cemetary and the Museo Nacional de Bellas Artes.
The apartment is on the top floor while the elevator only goes up to the floor right below it, and so there's one flight to walk --- if there is an accessibility concern.