ROAD TEST: BMW X5 M50i And X5 M Competition - CAR Magazine

Picture the scene: you’re at a concert of a musician you’ve long admired. There’s a palpable sense of expectation in the air. Then, the supporting act takes the stage and woos the crowd, to everyone’s surprise. It’ll be a tough act for the main entertainer to follow … 

This aptly described our feelings when the X5 M50i arrived at the CAR’s offices for testing a few days ahead of the X5 M. We were instantly enamoured with the M Performance variant; so much so, it cast doubt on whether the X5 M’s additional R1 million-odd would be money well spent. 

However, let’s not jump to conclusions quite yet; first, some background. When BMW South Africa initially launched the current X5 – remember, it’s CAR’s reigning champion in the Top 12 Best Buys Luxury SUV/Crossover category – it offered just the xDrive30d and M50d. The range has since expanded to include the eco-focused 45e plug-in hybrid plus the two variants you see here, the M50i and X5 M Competition (the only M-bespoke derivative we’ll get. BMW SA cites the reason as higher customer demand for Competition models). 

Both apex models make use of the brand’s turbocharged 4,4-litre V8 sending power (and identical maximum torque) to all four wheels through an eight-speed ZF automatic transmission. Each received extensive suspension upgrades and is lavishly equipped and priced accordingly. We’ve broadly covered the X5’s interior, styling and ride/handling balance in previous tests, so here we’ll focus on characteristics which set these two performance SUVs apart. Let the games begin.        

On the test strip                   

We lined up the M50i. Offering  390 kW and a brawny 750 N.m to propel nearly 2,3 tonnes of SUV, the V8’s crankcase, cylinder barrels, pistons, crankshaft and head have all been fettled. BMW’s engineers also enlarged the two turbochargers nestled between the cylinder banks in the V and tweaked the Valvetronic valve control and variable double Vanos camshaft control. 

The result is an impressive sprint from 0-100 km/h in just 4,62 seconds – 0,01 seconds quicker than the sportier 405 kW Range Rover Velar SVA – and an effortlessly swift 80-120 km/h leap in just 2,94 seconds. “Effortless” is the crucial word here. The V8 shrugs off the X5’s portliness,     offering instant get-up-and-go from just 1 500 r/min all the way to the redline. It melds seamlessly with the ZF ‘box, which shifts at exactly the right moments to perfectly balance the request for more performance with stellar  refinement. Pop the drivetrain- management system into Sport or Sport Plus, though, and the V8 clears its throat before bellowing forth a spine-tingling roar. It sounds fabulous even if it’s augmented through the speakers.

 

Then the X5 M inched towards the start line for its sprint testing, leapt away and burst through the 100 km/h barrier 3,77 seconds later. It’s the quickest-accelerating SUV we’ve ever tested and bests BMW’s claim of 3,8 seconds. From 80 km/h to the national speed limit? A mere 2,41 seconds. If  effortless describes the M50i, “astonishing” aptly explains the X5 M’s performance. 

Along with the changes wrought to the M50i’s V8, the M’s version of the 4,4-litre gains a cross-bank exhaust manifold said to virtually eliminate turbo lag. It also sports a model-specific exhaust system featuring dual-branch pipework with high-capacity silencers, electronically controlled flaps and four 100 mm tailpipes sited in pairs either side of the rear apron. 

It’s odd, then, that the X5 M is less aurally appealing than the M50i. The former is certainly loud on start-up – too loud for some neighbours, we’d wager – but the V8 settles into a subdued idle and never really hits the high notes, even with the exhaust button activated on the centre console. This is a perpetual criticism of M products using the otherwise-flawless V8. If you’re an audiophile, the M50i is best suited to tickle your sound receptors.

However, if you get a kick out of setting up a car to your needs, the X5 M is far more customisable. Everything from the drivetrain response to the swift gear changes, steering weighting and suspension firmness can be adjusted and saved for quick access via two M toggles on the fat-rimmed steering wheel. One tester questioned whether these M1 and M2 buttons are entirely necessary on an SUV, but such is the wish of the buyers. 

Curiously, the M50i, with its smaller brake discs, performed better in our punishing 10-stop emergency-braking test, coming to a halt in an astounding 2,57-second average. The X5 M, with its M Compound brake system, needed 2,81 seconds. Feel and feedback on both, however, are excellent.

On a mountain pass

Far from the test strip, the differences are stark. While both models feature an M Dynamics suspension suite, the X5 M gains the Professional setup. Its Active M Differential can split torque longitudinally as well as laterally between the rear wheels to optimise traction in slippery conditions. As standard, it offers rear-wheel bias in 4WD mode, with the option of selecting 4WD sport mode that shifts even more drive aft to eliminate the push-on understeer so endemic to these heavy SUVs. 

It works brilliantly; cornering flat through long sweepers with very little lean into tight corners, the X5 M covers ground at an astonishing rate. Understeer is negligible and the rear-end can be provoked into a slight oversteer stance before exiting a corner cleanly and bolting to the next bend. The M Servotronic steering, offering little indication of the available grip levels, is quick and direct. In fact – though unsurprising considering the amount of hardware they share – the X5 M feels similar to an M5 Competition in the ruthless way it strings together corners. 

The M50i offers a notably more composed ride quality akin to that of a luxury car. There is some    pitter-patter, especially on this test unit’s 22-inch wheels, but generally, the M50i’s suspension does a fantastic job of smoothing over ruts and ridges. Coupled with excellent noise, vibration and harshness control owing to extensive sound deadening including double-glazing, the M50i is a wonderfully soothing conveyance. 

Yet, it does the S in SUV (or SAV, if you’re from BMW) proud, offering composed handling in Sport or Sport Plus mode. As there is quite a bit more body lean than in the X5 M, the driver has to be more conservative with approach speeds into corners, but that arguably elevates the M50i driving to more interactive levels. Switch everything back to Comfort and you can pootle home in a silent cocoon. It strikes a more appealing balance.  

In Their Cabins                     

Inside, the X5 M is set apart from the M50i by bespoke sports seats trimmed as standard in a combination of Merino leather and Alcantara (full hide is a no-cost option) and a model-specific digital instrumentation design. As you rightly expect considering the R2,6 million-plus price tag, the X5 M is lavishly equipped. The standout items include Nappa-leather trim on the facia and doors, a 16-speaker Harman Kardon audio system, laser lights, wireless smartphone charging and all manner of active and passive safety systems. 

Interestingly, the M50i nearly matches the M’s standard spec, only really sacrificing big-ticket items such as the Merino leather (optional; Vernasca trim is standard in a range of colour palettes), the laser lights (an R18 900 item), and the Harman Kardon option. Intriguingly, BMW SA offers an upgrade to a Bowers & Wilkins audio system equipped with 3D speakers in the roof for R72 500. That’s money better spent elsewhere, as the Harman Kardon configuration boasts punchy, crystal-clear audio. 

In terms of fit and finish, the X5 remains a frontrunner in this class, easily besting the newer Mercedes-Benz GLE’s interior for material richness and matching the Range Rover Sport’s sense of occasion. That said, the firm suspension on the X5 M unearthed myriad rattles and squeaks in this test vehicle. The M50i, meanwhile, didn’t utter a peep.