Car travel in Sicily

The highways are excellent and not particularly crowded. As in most old European cities, navigation and parking can be challenging in the cities.

Zero deductible is advisable. Also make sure that you have a closed trunk for your luggage.

The streets can be very narrow to navigate in spots (like in Taormina) and some touristed sites have had periodic car break-ins (i.e. Segesta).

The major difficulty you will encounter driving in Sicily is the quirky nature of the signage. I would strongly advise you, therefore, to take a gps; but have a good map, as well, for back-up. I and others have posted elsewhere about the ins and outs of driving in Italy and about the use of a gps. Look on the Grafitti Wall under "Driving Europe Crazy." If you don't find my detailed account of driving with a gps in Sicily, you can pm me or just put in a reply on this thread. I also was very unhappy with my experience renting from Hertz (arranged through AutoEurope), which I have also written up. I'd go so far as to say that if I were to rent a car in Italy again, I would not accept a Hertz rental from AutoEurope.

No problem driving in Sicily. However avoid having a car while in Palermo due to traffic congestion. If you rent in Palermo just do so the morning you head out of town.
GPS is useful, however I survived with a map only. Roads are good and freeways even better (fairly new in some stretches).
Regarding the bad experience with Hertz by the previous poster I. Can tell you that I have had a bad experience renting cars in Italy with virtually any company (Avis, Europcar, Hertz, Sicilybycar, you name it). You just have to take it as an additional cost of travel. I suggest to buy azero deductible insurance plan (they'll try to charge you for dings otherwise, even if non existing). Another trick they'll try to pull is to charge you for the gas, even if you return it full. Since you see that charge only when you come home and it's difficult to fight it, you might as well return it empty. At least they'll charge you for a good reason. Also purchase an economy or compact car. Sometimes I have paid more for intermediates but they still gave me a compact because they had no intermediates available.

To avoid the return gas charge, for any rental anywhere, I do the final fill-up and pay using the same credit card that I use to pay the car rental company.

I have easily and successfully challenged a credit card charge, from a rental returned in Barcelona, simply by pointing out the date and time of the gas station charge to the cc rep.. The rental company gas charge was immediately reversed by Visa with no fuss whatsoever.

I rented a car from Hertz for one day, driving from Agrigento to Siracusa, by way of the Villa Romana del Casale. Despite my slight moment of panic at the very beginning - the car was parallel parked facing up a hill, with a stick shift - it was very easy. We had reserved a compact which they did not have onsite, so we got upgraded to a slightly larger car at no charge since we had a long drive [maybe they felt sorry for daughter and me]. I filled the tank just about 5 or 10 miles before we turned it in and we saw no extra charges for gas, dings, or anything. In fact, the man at the return counter even printed out a map to help us find our hotel. Traffic overall was fairly light in mid-May for us, except going through Piazza Armerina where we ran into a lot of traffic and some confusing road signs. have a great trip!