When in Europe, I always rent from Sixt. This is one of the worlds largest car rental companies and the only one that is European (German) rather than American. Sixt offers luxury and top service (they used to rent Mercedes cars only few decades ago). Sixt is not a low-cost car rental but is also not seriously overpriced. Usually, you will get similar price from Sixt and Hertz under the same conditions. In Italy, English (or any other foreign language for that matter) can be a problem, even in the hotel or at car rental counter. I sometimes manage to communicate in French but at Sixt Fiumicino the language skills of local attendants were more than satisfactory. We were not waiting - 6 or 7 minutes at most, and then got our car. We declined an upgrade but you have no choice with the CDW which is included in Italy in every car rental by law. This made the price much higher than originally stated but it's the same with every Italian car rental company. We had a small problem with the air condition later on and they were very helpful in bringing another car to our hotel within two hours.