We really liked the location, there were a ton of really great tapas and pintxos bars within a 5 minute walk, plus grocery stores, easy access to the metro, La Rambla, and several top-quality museums/viewpoints. Ana gave us a sheet of recommendations for the area and neighborhoods throughout Barcelona; I texted her a few times during our stay to ask for tips and all her suggestions were fantastic.
Despite the proximity to tons of activities and lively bars, the only sound from outside the flat itself was the upstairs neighbor moving around, which can't really be helped.
Be aware that the building and flat aren't exactly built for tall people, so you'll need to watch your head if you're over 6 feet, and you'll be sleeping diagonally in the bed if you're 6'5'' like my boyfriend. The flat is small, and there's not a ton of storage, but we didn't really care - the location was totally worth it.
The amount of amenities we were provided with was spot on for our stay (3 days), plenty of body soap, dish soap, laundry detergent, shampoo, hand soap, and toilet paper. However, there was no conditioner or body lotion, if that's something that matters to you..bring your own.
While we were there, we had some trouble with our light and fan being controlled by a master switch, presumably in the other unit next door, which we didn't really care about during the day but it wound up interrupting our sleep a lot our last night there. Ana was super gracious about looking into it, and I imagine it has already been fixed for whoever stays there next.