I'm not sure about urban areas, but the further out you go, the worse Telstra (3G coverage) gets. I live about 100k's outside of Adelaide and Optus is superior

I'm not sure about urban areas, but the further out you go, the worse Telstra (3G coverage) gets. I live about 100k's outside of Adelaide and Optus is superior by far to Telstra and Vodafone (3). All their prices and plans for mobile data are atrocious, so we go with Internode, who lease from Optus and whose prices, while still atrocious, are overall better. And everything about Internode, especially their customer service, is better. My two cents.