I know that Cook's Illustrated magazine recommends DaVinci brand olive oil as the best tasting. I think that, similar to wine, it is a personal taste preference as much as anything. Some are more peppery, fruity, grassy, etc. Taste matters most on salads or bread, for cooking you can use something cheaper. We try to use organic for high-fat content things as pesticides travel in fat more readily (as I understand it) so there are not many choices in the organic brands.