I staid 3 nights with my 3 friends. The appartment was very clean and comfortable. The bedrooms are spacious and the beds were also great.
The metro stations are a bit far away from the appartment but you can easily go there by walk. If you come in BCN with the train, you can reach the train station by walk too.
The area is calm, particularly at night.
I recommand this appartment if you travel by group and if you look for a comfortable and safe place to stay.