Highly recommended!
The apartment was spacious, very clean and comfortable. As far as Barcelona goes I also don't think you can do any better location wise. The apartment is situated next to a big park in a good area with great vibes just far enough from the main, sometimes overly congested, tourist streets. Also if you are a runner, you have easy access to the beach promenade as well as said park.
Katarina was the perfect host. She was welcoming, helpful and accommodating.
Barcelona is an awesome city and when I go back there I wouldn't think twice about booking my stay @ Katarina's place.