Great place and location for a couple! we spent a week in Buenos Aires, and most of the attractions were walkable from Gaston's place. The washing machine and AC were very handy, since it was very hot. There is a fully equipped kitchen, if you want to cook.
If you like coffee, icecream and Sangria- you are in luck: the best coffee shop (Lattente), best icecream and chocolate shop (Rapanui) and best Sangria &tapas bar (Lady Madrid) are within 2-3 minutes walking. We highly recommend Gaston's place!