Even though the reviews were excellent and our expectations were high, Guille's place was even better than we had hoped.
The location is incredible. Very quiet, very central, and close to lots of stores and great restaurants. For context, it is beside the Park Hyatt, a block from the Sofitel and two blocks from the Four Seasons, so the same locale as the best hotels in the city.
The apartment is nicely decorated, and has everything we needed. We were able to work during the day (the wifi is excellent), cook (the kitchen has all the utensils you need for light meals and there's a grocery store nearby), and we slept well at night (the beds were comfortable and the AC was good).
Guille was an excellent host. He gave us lots of helpful tips and was always available if we had any questions. He also checked in regularly to ensure we had everything we needed.
If you are in Buenos Aires for an extended length of time, this is the perfect home away from home.