We enjoyed our stay at Flor's apartment a lot. It is well equipped, nicely decorated, and well located (a few meters from Poble Sec station and a BSM parking - we used the parclick.com passes which were great value). I didn't get a chance to meet Flor, but her husband Raul was really responsive and flexible.
Regarding the noise, Flor just added double glass windows in each of the 3 bedrooms, and we slept very well each night. (As they did not add double glass windows in the living room, we could compare with and without double glass window, and the noise difference is noticeable.
We would definitely stay at Flor's apartment again if we come back to Barcelona.