Our stay at the "Sweet Suite" was excellent. The appartment is in a quiet street but near the Petersdom. You can walk there in 10 Minutes. Massimo was very nice and welcomed us with a basket of fruit, water and clever tips.
Near the appartment are delicious restaurants, supermarkets and a luggage drop-off, which is nice for the last day.
One tip (so you don't waste as much time as we did) if you go by taxi they have fixed prices (Ciampino 30€ and Fumiciano 48€). If you go by train and bus you will pay the same but have much longer travel time.
If you want to live nice and in a beautiful area in Vatican area then book this appartment.