The apartment is app 15 minutes walking distance from the Termini station. This is helpful as during your stay you would definitely use some metro (both A and B) / train lines.
The area is less crowded by people which we appreciated after whole day of sightseeing in the city center. Moreover, nice restaurants / bars can be found in the vicinity with classic Italian food and wine.
During our stay in September, the weather was still hot with the nights quite warm - the air-conditioning in the bedroom was a must. Don't count on opened window during the night (alternative to AC) as the nearby railway could be a bit noisy (depends on how deep you fall asleep :D )
But this was no issue for us, we enjoyed the stay anyway and would recommend this apartment to you as well.