Location is awesome — the city centre, but mostly locals in the area. I loved this! Plenty of supermarkets, good market nearby. If you are with kids — there are several playgrounds just 3-5 min walk, or you can hop on V19 bus and get to Ciutadella park in 15 min (30-35 min walking).
The apartment is 100% comfortable and spacious. With the gas heater, you always have hot water and can use the fast and effective heating system if you need it.
The apartment (and building) is very quiet with one exception — in the small bedroom you will hear neighbours opening and closing elevator doors, and these are really loud (the elevator is old and funny). It is probably ok for adults, but we planned it as a bedroom for kids, and they couldn't sleep there (we moved the cots to our bedroom, and it was ok).
Carlos is an excellent host — always in touch and very caring.
Definitely, recommend the apartment.