We had a very nice stay at José Luis's place. The flat is ideally situated for us, in a quieter place than downtown Barcelona but close to Cosmo Caixa or Parc Guell and Tibidabo, which are great places to visit as a family. The subway is just nearby and the main road that leads to the beaches very easy to catch from there as well.
Excellent location, comfortable, clean...just don't hesitate !