My friend and I both booked a single room and were put in a room of 8. The second night, we were outnumbered by males, even though the website said nothing about the rooms being co-ed. This needs to be mentioned on the website so that people know ahead of time. We left the hostel and found a hotel for the rest of our trip.
There are no locks on any of the doors, including the two doors to get you into the hostel from the street. This is a bit concerning. I get that Poland is safe, but if people staying there don't feel safe, you need to put locks on the doors. You never know who could walk into the hostel, it could be someone dangerous.
It's also pretty hard to find. Wish there was a sign on the street telling you in was in that alcove.