This is a cozy apartment in a perfect location. Everything we wanted to do was within 30 minutes walking distance, and there's a metro stop very nearby as well. Lots of great little coffee shops, bars, and markets in the neighborhood too!
Our host was very helpful and answered all our questions quickly, and offered advice on things to do while in Barcelona. We were even allowed to leave our bags in the flat for a couple hours on the day we checked out, which was a huge help.
The space was very comfortable, but we did have to deal with a pretty strong sewage smell in the bathroom which wasn't always pleasant. Otherwise, it was clean and welcoming.
If location is your top priority, Mireia and Maria's place is a great choice!