Mercedes-Benz Gls450 vs BMW XM

What's the difference?

The ‘Upper Large SUV over $120K’ segment of the Aussie new-car market is what you might call the top end of town, not only in terms of the extravagant models available but also their purchase prices, which stretch well into six figures and require monthly lease payments that rival home mortgages.

It’s where you’ll find some of the most prestigious marques in the automotive world including Rolls-Royce, Aston Martin, Bentley, Ferrari, Lamborghini, Range Rover, Lexus and BMW. And, of course, Mercedes-Benz with its big GLS which represents the flagship of the German manufacturer’s SUV fleet.

It was given a refresh in 2023 with cosmetic and multimedia upgrades along with powertrain enhancements, but there have only been minor changes since then. We were recently entrusted with the keys to the latest GLS to see if the ‘S-Class of SUVs’ leaves any room for improvement.

BMW’s new XM is a tricky customer to pigeon-hole. Yes, it’s a huge, super-lux SUV and, yes, it’s all-wheel drive and features a station-wagon layout.

But it’s also a M-car and that infers super high performance. Weighing in one the wrong side of 2700kg, however, makes that a difficult task for any engineer.

This car also left us wondering if perhaps the glory days of M Division sports cars and coupes might behind it and SUVs like this one represent the road ahead.

But fear not: The CEO of M Division himself, assured us that the XM is a showcase for what an M badge can do, rather than a mission statement for the brand.

So, with that in mind, does this car have the wow factor that places it somewhere between peak oligarch and a motor-show concept car? Does it move the goal posts for big luxury SUVs? Does it even matter that it’s a plug-in hybrid?