I stayed at Hostel Pisa for 2 separate nights, with a great first impression both times I checked in. If someone's already being served at reception, another staff member approaches you to ask if you're checking in. If you are, they give you the form to fill in while you wait. Once you're checked in, they give you a tour of the hostel and facilities as they direct you to your room.
Both nights I stayed in a 4-bed female-only room with en-suite, both of which were comfortable, spacious and clean with medium-sized lockers. The first night I was in 208, overlooking the outdoor bar, which stayed noisy well past the 2am close. On checking in the 2nd time, I explained the situation and my request to be in a room overlooking the front of the building was accommodated.
Both mornings I had a really good value breakfast, and one evening I did the all-you-can-eat buffet (lukewarm pizza and pasta unless you take from the dishes as soon as they come out the kitchen), which included an alcoholic or soft drink. I also did laundry, which was 5E each for washing and drying, and the dryer was fantastic.
The hostel is in a really good location - turn right out the train station and walk 7 mins. It's only 5mins on the train to the airport, or you can walk it in 20 mins. I would definitely recommend it here.