We stayed for five nights and are completely satisfied. The appartment is very close to the Coloseum. The next Metrostation (Cavour) can be reached within 5 minutes of walking, so it makes for a great place to explore the city. As it is situated below ground, the temperature is always very nice, even with nearly 40°C outside. The appartment offers everything you might need and has several supermarkets and a plethora of restaurants within walking distance.
Highly recommend!