This apartment was spotless and the host was amazing. He helped orient us to the city and explained the bus system as well as giving advice on dining options. We absolutely loved the A/C and the fact that there were fresh milk, juice, and other snacks free in the apartment when we arrived. We also loved the outdoor remote controlled shutters which were great for blocking out the light during sleeping. The apartment is secure and we were never worried about safety.
There is a balcony but it looks out over a grafitti covered above ground train system, so it's fine for a little fresh air but not a good view.
The location is just outside the Vatican wall but it is still a 20 minute walk to the Vatican entrance. To get to any of the most popular Rome sights you need to take a bus to the city center, which we found a bit inconvenient.
There are wonderful restaurants close by.
There is frequent noise from the train passing by in the evening which is mostly muted but can still be bothersome while you are trying to get to sleep. There are also bells that sound early in the morning and in the evening which I assume are from the Vatican. Obviously there is nothing that can be done about this outside noise, but if you are a light sleeper, it may be an issue. All in all, we felt like this was a great value for our money.