We had a great time at Ezequiel's place.
It's exactly a described and pictured, if not better. The flat is spacious, well equipped and has pretty much everything you'll need for your stay.
It's in a very cool part of town, with bars and coffee shops around the corner, and the more buzzy parts of Palermo within easy reach. The MALBA Museum of modern Latin American art is also a ten minute walk away and is highly recommended.
We walked and used the Metro (Subte) a lot - the nearest stations are about ten minutes walk. Taxis were also simple and easy to get from around the flat.
Ezequiel himself wasn't in town, but was very quick and efficient in answering our messages. His friend (also Ezequiel) helped with check in and check out, and was available for questions and advice, including how to change dollars at the best rate.
In summary, highly recommended place in a great location in a city We are missing BA already.