We stayed for 3 nights in Papa Germano and it was a good experience.
The surroundings are a bit depressing, but you can quickly get to Republica which is a much nicer place. The Hostal itself is essentially functional, with kind personal that speaks english quite fluently, nice and clean rooms (the wc's have been recently rebuild and they look really neat), comfortable beds and pillows, even a TV (that we never used, but hey, it's there). There are PC's at the reception and the wifi works decently well.
The 5€ breakfast buffet option follows the philosophy of the Hostel: nothing remarkable for good or bad, variety and quality are ok, except for the coffee, which is essentially disgusting sullied water. There is a panneteria nearby (called 3P) that has amazing stuff (you should try their Margherita at least once) at very good prices ,so unless you are an avid early-morning eater I would recommend that option. At any rate, the in-hostel bf is still a solid alternative.
We had no problems with noise except for two times when the fire alarm rang, probably because some folks were smoking. Nothing to blame the Hostel for at any rate.
In conclusion: an average hostel that will cover your basic needs for a reasonable price (taking into account the location) and a nice staff that is always kindly available to answer to your requests. If you're in a trip with friends or your boy/girlfriend and don't require an specifically romantic setting, this is a good place to stay.