Great location close tot he Vatican and a few minutes away from the Ottaviano metro stop which take you everywhere.
There is also a parking garage 100m from the apartment, it is a bit expensive but very practical if you want your car to be safe during your stay, AnnaMaria also gave me all the tips to park on the street if needed.
The apartment is clean and the beds very comfrotable, it might be a bit noisy, but well, it is in Roma!