We enjoyed the time being in the apartment, the terrace was huge with a nice view.
However we missed some basic elements in the kitchen, like coffee, tea etc. The flat itself was perfect for 2 persons. We loved the easy check-in system.
All together we spent wonderful 4 days in Barcelona, we loved the city.
PS: You should take comfy shoes with you to able to climb to the apartment from the metro ;) Nice training!