Fantastic location, with everything at your doorstep and good connections to other parts of the city on foot or by Metro/Bus. Very well organized apartment with everything you need for a short or long stay. Monica was very responsive when we had questions, there's also a manager in the building during the mornings should you need something.
It's an apartment building in a busy area so you can hear neighbors and street noise from time to time, but that is normal for Barcelona in general. We stayed for a month, slept great, ate like kings, explored the city and really enjoyed our stay.