The ML420 CDI is beefier, way more economical, will realise a better resale value and removes that final weapon from the armoury of the committed petrolhead its even better to drive. The clincher is that Mercedes has priced the two cars at an identical £50,435. Big diesel engines make a great companion to luxury 4x4s and the Mercedes ML420 CDI benefits no end from just such a partnership.
With the ML420 CDI, you should get to within a couple of mpg of its quoted 25mpg figure without having to freewheel down hills. While this still wont make it the apple of the green brigades collective eye, its better than youd expect from something like a Ford Focus ST. Emissions arent eyewatering, with the big Merc returning 299g/km of carbon dioxide (ML500 319g/km).
The Mercedes ML420 CDI is an extremely capable car. Its unlikely to be taken off road but even when judged against road-biased rivals, it still makes a convincing case for itself. While it may not be the pick of the M-Class Range, it gives its direct opposition a real headache. Choices are only problematic when theyre not clear cut.
