We went to Barcelona primarily for sightseeing and the location of the apartment is great for that (Barcelona is great for walking around but you also have metro stop 5 min away)
The apartment was very clean and spacious and we had everything we needed for our 11-day stay.
Wifi is of good speed.
We didn't use airconditioning (February) but the heating was very efficient.
Despite proximity to the busy road it was quiet.
The apartment was easy to find and check-in/check-out.
The only disadvantage was a bad smell in one of the bathrooms (it didn't sread to the rest of the apartment) but that was about it.