What's in a flagship? As a torchbearer for its brand, it not only must bring more of everything found in the models positioned below it, it also must do everything better. Or so the thinking goes. Which makes it a curious—and controversial—decision for BMW's M performance group to choose a big, luxurious SUV, the 2023 XM plug-in hybrid, as both its new lead act and the first M-exclusive model since the M1 supercar of the 1970s. But these are the times we live in. Fortunately, they don't preclude such a vehicle from being surprisingly good to drive.
Quite the contrary. Today's crop of high-performance SUVs, from the Aston Martin DBX to the Lamborghini Urus to the Porsche Cayenne, offer stunning abilities bathed in varying degrees of opulence. Yet, as some M officials admitted before letting us drive an XM prototype in Austria, it doesn't make a lot of sense for inherently large, heavy, and utility-oriented vehicles to be focused purely on speed. Better to concentrate on nailing a good ride-and-handling balance than setting a new Nürburgring lap record.
Broadly speaking at this stage in the XM's development (sales won't commence until early next year), it comes across as a spacious grand-touring machine imbued with the nuanced tactility that is rare among the M brand's contemporary offerings, which for all their speed and capability can often feel edgy and aloof. Tellingly, BMW M's engineers cited both the Urus and the statelier Bentley Bentayga as initial inspirations for their flagship's road manners—decidedly athletic but not hardcore.
While the prototype we drove was still clad in extensive camouflage inside and out—a good or bad thing, depending on your views of the XM concept that the production model should closely mimic in design—BMW did reveal more of the XM's technical makeup. Compared to its closest mechanical relatives, the X5 M and X6 M, the XM sits lower, and its snout stretches longer from dash to axle. Although the XM will be two rows only, its length and wheelbase—spanning 203.3 and 122.2 inches, respectively—are closer to those of the three-row X7's. Its unibody is mostly steel draped with aluminum panels, and we expect its curb weight to be around 6000 pounds, split close to 50/50 front to rear.
Under the hood is an M-massaged version of BMW's latest twin-turbo 4.4-liter V-8 that debuted in the updated 2023 X7 and redesigned 7-series. Hybrid assistance is via an electric motor sandwiched between the engine and the excellent ZF eight-speed automatic transmission, with the combined output of the vehicle we drove amounting to 644 horsepower and 590 pound-feet of torque—strong but not segment-leading figures, though BMW promises a more powerful setup with closer to the concept's 750 horses also will be available. An all-wheel-drive system that can route up to 100 percent of the power to the rear wheels is standard, as is an electronically controlled limited-slip rear differential. The fuel tank is situated under the spacious cargo area, making for a somewhat high liftover height, and a lithium-ion battery pack of as-yet-unknown capacity is stashed under the rear seat. Electric-only range is estimated at 50 miles in Europe's generous WLTP cycle but should still be sufficiently usable by EPA standards.
Our drive was relatively brief on damp mountain roads surrounding Austria's Salzburgring racetrack, just over the German border. Although the XM's engine can rev above 7000 rpm, we didn't need to spin it hard to be squished into the seatback, thanks to the electric motor's instant low-end torque that almost seamlessly blends into the V-8's powerband. With the 60-mph time of the model we drove likely in the 3.5-second range, we'll call it unassumingly quick. Even in EV mode there's enough thrust to safely pull out into traffic; mash the accelerator past its detent, and the gas engine fires up for assistance. Being a modern BMW, the XM's expansive curved dash display offers a dizzying array of drive-mode settings, including drivetrain response, steering and brake-pedal effort, ride stiffness, regenerative braking intensity, and more. But even in Sport mode, the active exhaust system's internal-combustion fireworks were tempered, the aggressive growl of the V-8 sounding distant under the accompaniment of an electronic whir played through the audio system.
Far more compelling is the XM's chassis tuning, to which M engineers took an "old-school" approach. Despite its three-position adaptive dampers and front and rear 48-volt active anti-roll bars—a first for an M car—the XM's multilink front and rear suspensions are supported by steel coils rather than the air springs we expected to find. That made its combination of astute body control and comfortable ride compliance, at least compared to the X6 M Competition we also drove, all the more impressive. And this is while riding on the standard 22-inch Pirelli P Zero summer tires (21- and 23-inchers will be optional). Those rollers surround big six-piston front and four-piston rear brakes with cast-iron rotors, which smoothly took over from the regenerative braking system when we laid into the left pedal.
Better yet, the action of the XM's steering—linear, nicely weighted, and blessed with actual feedback—rewards its pilot in all the ways that its lesser siblings (and even some of the M brand's current coupes and sedans) do not. When pressed about this welcome responsiveness, M officials pointed to the model-specific suspension bushings in the XM's front end plus the unique programming for its variable-ratio steering rack that it shares with the comparatively darty X5 M and X6 M. But the effect is pronounced in bringing greater confidence and fun to the driver. Aided by rear-wheel steering hardware that can swivel up to 2.5 degrees, which makes the XM feel agile for its size yet eminently stable at higher speeds, the vibe from behind the wheel is reminiscent of the progressive helms that BMW traditionalists have been clamoring for the return of since the days of the E90 M3.
That this level of over-the-road satisfaction comes in a vehicle with a back seat that could pass for a cushy living-room sofa—partly a concession to the chauffeur-heavy Chinese market—does little to alleviate the head-scratching surrounding the XM's existence. That it's also a plug-in hybrid lends it as much novelty in this segment as additional flexibility. But as BMW's launchpad into the rarefied air of big-power SUVs costing well in excess of $100,000, it does drive with a cohesiveness that we hope filters down to other BMW models—exactly what you want from a flagship.