I enjoyed my stay at Flor and Max's house a lot! On the one hand, the room is really nice and clean and the are both great hosts. On the other hand, the neighborhood of Palermo has a lot to offer: most probably the densest offer of restaurants, bars and clothing shops, it is safe and there are lots of people on the street, awesome!
As others mentioned, I would definitely recommend you to attend Flor's Tango orchestra concert on Monday evenings, it was a really good performance at a nice as well as authentic venue!