Stayed for nearly 2 months in Marta's apartment while working at the University. The apartment is really nice and has all comforts of aircon, (very) high-speed internet, dishwasher and a big tv, all essential for a long stay. At a small extra cost the apartment was also cleaned every week.
The neighborhood is not touristy, but still lively with plenty of shops, supermarkets and bars and restaurants all within walking distance. It's only a 1min walk to the nearest metro station (place del centre) which will bring you in 10min into the city center, and for late nights returns there is a bus stop right in front the apartment building where the night bus stops.
Marta has been very helpful, always quick to respond to emails and and she can give you some good restaurant tips!