We stayed 5 days with our 3 children. It's a good value apartment in a good location (we loved seeing the Sagrada Familia each time we took the metro), in a building wholly managed by the same organization.
If you are planning to eat in, consider bringing with you a couple food items such as salt/pepper (you'll easily find supermarkets nearby). Light sleepers might also want to bring an eye/sleep mask, as the curtains in one of the rooms do not block the light perfectly. We did sleep well, though.
All in all, recommended!