I get about 9-10litres / 100km in bumper to bumper evening traffic from Sydney CBD to St Ives. I did burn 16 litres / 100km at the Nasho with some liberal use of the loud pedal!!
BTW - the trip counter is not that accurate, hell the speedo is not accurate. The GPS indicates that I am travelling 110km/h and the dial will show slightly above the 115km/h