Dealers in Australia are telling customers to use Premium Fuels as it will give better economy. The Economy was terrible. We dropped back to Unleaded Standard and after a couple of fill ups, economy improved and vehicle appeared to run smoother. We read the manual and it says there is no advantage to using Premium Fuels and in fact Ethanol Fuels are what it is tuned for. We started using E10 and performance and economy improved even more. Overall though the economy of the Dodge is not the best compared to most cars.