Pros: Location. This apartment is great for those who want to be in the heart of the city. It is easy to walk around within Barcelona and Placa Catalunya is 1 minute away for public transportation to the airport, or to go outside the city. The decor is nice, the apartment is clean and has what you would need if you don't plan on staying inside much. Hosts are very communicative and responsive as well, and will greet you to show you everything you need upon arrival. Right by the gothic area, but the street itself is quiet.
Cons: Not necessarily anything truly bad about the apartment- but be advised it is a smaller (but sufficient) space, there is no TV (who needs one!), and no oven (again... who needs). It is also on the 4th floor so definitely requires guests easily capable of climbing up quite a ways.
Overall: It is worth it for those looking for something clean, central, with great, communicative hosts. It was just what I was looking for!