Great location if you need to be in or near the Vatican during your stay in Rome.
The apartment was spacious enough for our large group (11 people). The interior of the apartment is very modern but, not surprisingly (you're in Rome!), the building is not. This was not an issue for us, other than the small/slow elevator (some of us opted to walk up the stairs to the 5th floor when we came back in groups of more than four at a time).
We had some issues with the plumbing while we were there (heater broke, the temporary replacement wasn't sufficient and there were issues with the "final" replacement) but Maurizio was VERY responsive, made sure things were fixed for us and even sent a cleaning crew to make sure the repairs didn't affect the cleanliness of the place. It seems the three bathrooms were not in the original design of the apartment and I will agree with some of the other comments I saw about the "little things" (like soap trays in the showers) that could have improved the bathrooms.