The thing with these suggestions is, they are all anecdotical from a single point in time and (market) space. I remember having read here somewhere, some time ago that maroccan or tunesian olive oil would be very good also, presumably because it isn't under the pressure of massive demand, so less incentive to fraud around it. Since decades this is a topic in consumer testing magazines and public television, and i can't remember anytime they didn't find at least one third fradulent. There are documentations out there, where they travel to Italy, speak with the local farmers, dealers, police and local government to get to root of this problem, and all involved parties (at least on the record) see it as a large problem too. Yet it is persistent.