The stay exceeded my expectations.
The hostel is modern and very clean. The inner courtyard gives a lot of seating opportunities beside the tables in the lobby. Moreover, I was surprised by how tidy and clean the room and bathroom were (compared to my prior experience with hostels). The people at the reception were welcoming, attentive and pleasant to talk to, even as conversation partners when taking a drink at the bar right next to the reception.
I would definitely recommend Nena hostel and go there again myself. :)