Don't be so sure about the holdens and fords! They use many different types of late model cars in victoria. Their favourite seems to be the subaru forester because the radar detection device fits perfectly in the space in the front bumper bar- so on a bright, clear day, when a flash device is not required, you can't tell it's a camera until you've passed the car.
One thing though, there MUST be a human operator in the car, so if the parked car has no occupants then it can't be a speed/ revenue camera!!
335i | 6MT | SG | Jade Grey | Poplar Grain Grey | 19" 230 rims | Sunroof | NAV with TV & voice control | HiFi | Sport Suspension | Rear Sunblind | 35% tints