Everyone who works there is very nice. They understand Spanish also, if you need to know this, and they speak very good English. It was my first experience in a hostel and it was a good one. My advice for future guests is that you bring your own towel and hygiene products, plugs for your ears so you can sleep better (as the rooms are shared and everyone has different waking and sleeping times) and a sleeping mask, so the light doesn't bother you as the room doesn't have a curtain.
There's a fridge and an equipped kitchen and also a locker where you can leave your valuable stuff and be sure they will be safe! I really valued that.
If I ever go back to Milan and need a hostel, I'm sure I'll stay again there!