We stayed 3 nights at Roma Hostel and had a very good time! The room was clean, with a comfortable bed and the location offered the opportunity to get to the most tourist places by walking. Maybe a note for the room 3: The neighbor watched TV everyday from 7:30am on a very high volume so we woke up by the noice. We didn't bother because we like to stand up early, but if you like to sleep a bit longer than make sure to get another room, there you might not get waked up by TV sound :)
All in all we had a wonderful time in Rome and the accommodation was perfect for our expectations.