Nice hostel, but too cold! The heating system is awful and the windows are old and/or broken.
Apart from the fact my boyfriend broke up with me there (and I had to look for another hostel in the last night), the place is really good. I'd just suggest a microwave in the kitchen.
I really enjoyed the hostel. Matt and the other staff members are so friendly that I felt 100% comfortable as if it was my own home. I highly recommend it to anyone visiting Berlin.