From the BMW press release:
"To ensure maximum cost effectiveness, the turbocharged, six-cylinder diesel powered BMW 530d was selected. It will be presented to Victoria Police in an entry-level specification, eschewing some of the higher-end luxuries found on the regular production model in favour of a factory-fitted ‘police pack’ which prepares the vehicle for heavy-duty operations. Similarly-equipped BMW 5 Series vehicles have long been part of European police forces, displaying a high level of technology with ample performance in emergency situations.
The first BMW 530d Victoria Police Highway Patrol vehicles are expected to be operational by early-2018."
Overall, I think this is a great alternative to the end-of-life Australian Ford Falcon and Holden Commodore. The civilian 530d has a stated fuel economy of 4.7L/100km and acceleration of 5.7 seconds from 0-100 km/h, which is equivalent to the average performance car today, and should be adequate for high-speed police chases. Whilst the fuel economy figure clearly won't be matched by 530d's undertaking highway patrol duties, it will nevertheless be substantially better than its Ford and Holden predecessors.
I wonder, however, what the maintenance and parts replacement costs for these vehicles will be. I wouldn't be surprised if Victoria Police has reached a special agreement for a discount given how expensive these costs normally are, compared to the Commodore and Falcon.
I would also suspect that the new Kia Stinger will give the 5-Series strong competition for use as a police vehicle given its lower cost, similar size and performance, and Kia's eagerness for the Stinger to be used as a police vehicle.