We stayed 2 nights. On the plus side, it's near several Rome attractions, including the Collisium and the Roman Forum, and the hop on hop off busses. But even our walk to Santa Maria Maggiore was only 15 min. Google maps works well to get around on foot! Check in was easy... they asked what time we would be arriving and although we got there early, our room was ready. The front doorbell works! Ring it and the owner comes down to get you! The inn owner was very good at explaining all the locks (there are 3 of them to get into the hotel!) and repeated himself to be sure! Room was clean and relatively quiet. And the AC worked fine although never got real cold.
It's an old building so don't expect the Ritz. Lots of restaurants nearby.
As others have mentioned, the beds are hard but they all were throughout Italy. The towels were somewhat scratchy but the bed linens were fine. Extra pillows and blankets were stored in a cabinet.
If you're visiting Rome to see the sites, i recommend the Nicolas inn!!!