This apartment is beautiful. The best part is of course the location - bang in the middle of centre of Catalunya, right next to the Apple Store and Adidas store. The flat is great, absolutely neat and clean. Basic amenities are made available and you'll feel like you're in your own house. The wifi works great. It's great for a family with kids.
We faced a few problems with the air conditioning as they would shut off automatically due to a voltage problem in the apartment. Also, there's no tea, sugar, salt, detergent etc already available. You'll have to buy or depend on if the last people have left something behind.
All in all, it's a great apartment and you should definitely book it.
Also, Marisa from the company was of great help and gave valuable info too.