I travelled here solo over Easter and reading some of the reviews on here beforehand slagging this place, I was slightly nervous. I shouldn't have worried!
Agreed, it's not a 5 star hotel so if you are expecting that, look elsewhere. If you want absolutely peace & quiet, look for a remote location, not town center. This is a quirky, characterful little flat in Barcelona's old town, historic with lots of original features, so do expect some creaking/noises. It's 5min from La Rambla, in a very busy location, however I didn't find the bustley noise disturbing during practice and it was quiet at night. Everyone who stayed there during the same time was respectful of the 10pm night-time.
The dishes served during morning brunch were delicious, however a bit more variety would have been nice - maybe add some yoghurt or a few extras from a more continental breakfast (eggs, toast). It was nice to chat with everyone over breakfast & make plans together. There was a sense of community which I appreciated as I was travelling alone. During my time here, pretty much everyone was female & travelling solo.
My bedroom was basic but spacious (shared twin room). Could be improved slightly by maybe having a second mirror in the room so I don't have to walk into someone else's space to use it. And maybe some more storage space / stools in the bathroom to leave clothes when showering. There's a hairdryer and some basic toiletries if you forget anything.
I enjoyed the yoga on the rooftop in the fresh air - there were different teachers, some a bit more advanced than others but you should be fine as an intermediate. The equipment provided (mats, blocks, blankets) was fine but maybe bring your own if you're super fussy.
Overall, the location is great & central, everyone was super friendly, the teachers were helpful and gave tips on what to do & see. I felt safe here and easily met like-minded new friends. Would definitely go back. A must try nearby is Chök - a little chocolatier just down the road with the most delicious pralines, donuts and pastries.