I had a very pleasant experience with SIXT rental car at Catania airport. I came to them as the last minute change as Locauto/Alamo customer service was horrendous and even paying for a full coverage would have left you at being liable for over $2300 in case of a theft in Catania or Catania Province.
SIXT car agents were polite, understanding, and knowledgeable. Not only SIXT covers the theft EVERYWHERE in Sicily, they got me a better deal on a car. Had I known that, I would have booked the car with them from the start and avoided unnecessary distress caused by Locauto company. If you need a great customer service with a great car deal, rent from SIXT!