Our experience was great with Sixt at this location. We arrived to get our car but there was an hour delay to get the specific one that we rented, we got offered an upgrade to an electric car which didn't really suited our needs so we waited. Because of the wait we got offered another upgrade to a cabrio and it was a really nice car to travel along Tuscany. Diana was super nice and helpful, explained us all necessary things such as protection packages and directions and tips with parking and the ztl of the area. The pickup and dropoff went smoothly. I really liked the out of business hours drop off option. We just went there around midnight on our last day and parked the car in a nearby garage and we saved one night worth of parking fees. (Approximately 20-30 € in that area)
Overall I would totally recommend this sixt rent a car location.
A word of advice if you rent a car in this area is to get the protection because the driving conditions are not ideal. 5 minutes after we rolled out we got cut off and yelled at several times. Fortunately we managed to avoid collusions but it's a matter of reflexes.