The best thing about this place is the staff, how they welcome you and how it is very essy to talk to them. They help you out with anything, and you feel like nothing about the stay at the hostel is stressful when it comes to checking in, leaving your things, eating breakfast and so on, and therefore you can focus on your activites in Paris.
However, I would say that staying in the common rooms with 6-8 people is a bit of a downer. I had never slept like that before, and I felt really awkward coming back to the hostem at 00:45 and how was I supposed to brush my teeth and find my things when everyone was sleeping? I felt very out of place and as someone annoying, but I had to do those things before bed. Also I have some needs due to health concerns that makes my bedtime routine a bit more noisy than usual, which made me feel very annoying.. however, since I slept in late, some of the others did not and three or four people had their alarms on for 7 in the morning. But after they turned off their alarms, no one got up? It was very annoying to me, because as a light sleeper I would just have to get up because I cannot fall alseep again.
So while I probably woke some people in the night, I was awoken in the morning too. And I constantly felt like I was making too much noise. Also, the air quality is really bad during the night because you sleep in a small area with thick curtains and no ventilation, which made my head hurt in the morning. You also need to bring your own towels and padlock for the big lockers.
If you are a little shy and awkward like me, or have any health concerns, I would recommend a single bedroom.
Otherwise a good location, close to the metro, and staff was supreme! :)