I see what the Water Corp is getting at here; and if you want a general overview of the products that are in the market place at the moment like the ones Bunnings, Masters and some irrigation shops use you would probably be on the right track.
However I have have found it too often this season that there have been a lot of places under watering as they have been following the ads on TV. You really need to know your how your system has been set up and what nozzles have been used in the process, as some sprinklers need an hour to deliver the same amount of water another only needs 10 minutes.
To better understand you sprinkler run times have a look at the following and see what will work best for you and your green spaces around your home.