Which used Mercedes M Class 4x4 should I buy?
For now, just about the only place you'll find a used example of this version of the M-Class is a Mercedes dealer or through a Mercedes Direct outlet.
However, wherever you look, go for a diesel-powered model, which has the advantages of better fuel economy and stronger low-down pull. The ML320 CDI, in particular, is a gem, with a good blend of performance and economy. By comparison, the ML280 CDI feels a little weak, and the ML420 CDI is just too expensive.
Likewise, if you prefer a petrol engine, don't bother with the expensive ML500. The basic ML350 drives well enough and costs much less.
Every version is lavishly equipped, with cruise and climate controls, all-round electric windows and alloy wheels, so the basic trim will be plenty for most people. However, you could upgrade to SE, which brings leather upholstery and metallic paint, or Sport, with its bigger wheels and sportier interior trim.