First of all, both Recoleta and Palermo are big barrios. Palermo is actually huge. To try to describe either in terms of quiet or noisy is ridiculous. Each barrio has very quiet places (e.g., the island in Recoleta), as well as very noisy places (e.g. the corner of Juncal and Arenales in Recoleta).Contrafrente apartments are a good idea, but not always as quiet as you might expect. There are lots of other sources on noise in the city besides vehicles, and the wrong contrafrente apartment can expose you noise that is every big as bothersome as vehicles.Bottom line is, don't try to pick your barrio, building, or room from wherever you are. You need to get here and wear out some shoe leather looking at various places in various neighborhoods.Personally, if I were coming down and knew what I know now, I wouldn't consider staying in either Recoleta or Palermo, but hey, it's your life.