The Mercedes ML 250’s price places it shoulder to shoulder with entry-level versions of all of its main competitors. It’s a formidable list: the Range Rover Sport, Porsche Cayenne and BMW X5 all feature in it, and they each come with superior performance thanks to the 3.0-litre diesel engines that prop up their respective ranges. Of course, this issue is addressed by the ML 350 CDI, which matches its equivalent 3.0 TDI rivals for power and torque.
The ML 250’s predictable trump card is the fuel efficiency derived from its comparative lack of cylinders.
With 44.8mpg claimed (we achieved 40.9mpg on our touring run), it is the class leader, and if you choose to have the optional 93-litre tank fitted, Mercedes reckons that you could clock up as many as 930 miles between refills.
Although that’s doubtlessly a little optimistic, the CO2 emissions are laid out in irrefutable black and white and they, too, place the ML 250 out in front of the field. At 165g/km, it finds itself in VED band G, three better than its J-banded rivals. Clearly, that represents a significant annual saving, but from the point of view of showroom tax it also means that putting a Mercedes on the drive is fractionally cheaper than the alternatives.
Of course, choosing the ML 350, and you'll gain two more cylinders and an additional 844cc with predictable results. Mercedes claims an official fuel consumption figure of 39.2mpg - 5.6mpg less than the ML 250. Road tax jumps from band G to band J. And given the relatively small performance differential, we can't understand why you'd plump for the larger engine.
Opting for the ML63 AMG predictably has a catastrophic effect on running costs. It’s claimed MPG isn’t far off half that of the ML 250’s at 23.9mpg, and it emits 276g/km of C02. Still, if you can afford the flagship's £82,995, you should have the resources to keep it running.