Pop Quiz: 2015 BMW X5M or X6M?

When you have two cars that are this similar and this nichey, there’s really no sense in covering every detail that we have already previewed in our BMW X6M First Drive. So we thought we would key in on what few differences there are between BMW’s more conventional X5M performance SUV (or SAV in BMW parlance, short for Sports Activity Vehicle) and the ballistic X6M crossover with its rakish, coupe inspired roofline (which BMW dubs a Sports Activity Coupe, or SAC – make of that what you will).

SAC vs SAV, long roof vs rakish profile, cargo space vs slightly less cargo space, which would win our theoretical autoTRADER dollars?

Both launch to 100 km/h in 4.2 seconds in the sharpest Sport+ mode, or cruise in Eco Pro mode and burn through fuel like just a small private jet.

1a. How do you like your family vehicles?

A. I like a little flair and panache.
B. I don’t want too much attention on my vehicle’s looks so I can drive like a maniac.

1b. Do you prefer:

A. Minecraft and Lego?
B. Kim Kardashian and Frank Gehry architecture?

If you’re into bricks and blocks and practical square shapes, well, no question the long roof and upright design of the X5M will speak to your linear sensibilities. Our tester flies under the radar thanks to its muted Donington Grey (beige, really), so it’s definitely the option that will blend in at the school drop-off or mall parking lot. And perhaps fly under the radar of local constabulary.

The X6M, with its sloping hatchback roofline offers some instant drama and plenty of attention in Long Beach blue metallic, drawing more attention to the aggro body kit and chromed fender vents. I may be in the minority, but it seems a car of this power and capability deserves to draw attention rather than fade to the background like a wallflower at the junior prom.

2. But they’re essentially the same under the hood, right?

A. Yes.
B. Yes.

No getting around this one, both the X5M and X6M come packing the same big gun: a 4.4L twin-turbo V8 making 567 hp at 6,000 and above and 553 lb-ft torque between 2,200 and 5,000 rpm. BMW boasts that it is “the most powerful engine ever developed by BMW for an all-wheel-drive vehicle,” harnessing a pair of twin-scroll turbochargers, cross-bank exhaust manifolds, Valvetronic variable valve timing and direct injection. Despite weights of 2,386 kg for the X5M and 2,352 kg for the X6M, both launch to 100 km/h in 4.2 seconds in the sharpest Sport+ mode, or cruise in Eco Pro mode and burn through fuel like just a small private jet at 12.1 L/100 km on the highway and 16.6 L/100 km in the city.

I favoured pumping the extra gas and planting my foot to the firewall to see how the eight-speed transmission holds gears when under the gun, and the fortified AWD system distributing the torque to the four corners for blitzing away from lights and flicking the left paddle shifter in advance of corners and hearing the snarl of the downshifts as I searched for their limits and behaviour. 

3. Are there any performance differences at all?

A. Not that you’d notice.
B. Well, actually…

While the powertrains are a matching set, BMW has injected some differences when it comes to the X6’s chassis. While they share the same 2,933-mm wheelbase, 195-mm ride height and same front and rear tracks, the X6 is lower, longer and slightly wider. And whether it was the frequency with which I reached for the Sport+ mode because of the more sporty styling or that there was actually a little more bite on turn-in and stability in corners is something that would take a more expert driver to guarantee, I could swear that the X6 was simply sharper and flatter in the corners, and more cohesive dynamically that made me more eager to tease out its performance.

The X5 certainly cornered and took a line with greater ease than almost any SUV I’ve ever encountered (the Cayenne GTS being the most notable exception), but there seemed to be a bit more dive under braking and a touch more body roll, though this was not a carefully administered back-to-back track testing session. Just a gut feeling with all the psychological baggage I brought to the table because of my affinity for the X6 mojo.

4. How much more practical does that boxy shape make it?

A. All the difference in the world.
B. I can still fit all the golf clubs I need to take to the club.

If you find yourself frequently transporting dishwashers, Louis XIV chairs or dog kennels, then there is no question the taller loading bay of the X5 will prove superior. But if your standard cargo is a few sets of golf clubs, the week’s groceries and a stroller or the finest kibble for your dog, the X6’s 550 L capacity is only 100 shy of the X5’s 650 with the seats up, though its disadvantage grows to over 300 for all-out hauling with the rear seats stowed (1,525 vs 1,870) and the X5 also has a nifty fold-down section of the split tailgate to ease loading. However, aside from the height of the cargo bay, the X6’s depth and width are virtually identical, offer the same 40/20/40 split-folding flexibility, and I found the usable space (below the cargo cover) equally accommodating.

Only the tallest drivers will detect a slight headroom disadvantage in the X6, while the rear seats are admittedly a tad more confining, it would take a larger than average adult to feel cramped by the X6’s rear seats. However, the X6’s rear seats are optimized for four-person comfort, with a raised centre hump and deeper scalloping to envelop you in the rich leather, while LATCH anchors are concealed behind zippered slots. No question the X5 is designed with a bit more family-friendly practicality, while BMW envisioned four adults going out for a night on the town or up to the slopes or country club.

5. So, with the added practicality, the X5 costs more, right?

A. Nope, what a ripoff.
B. I’m not worried about the price.

Despite equal levels of refinement, technology and luxury, the X6 is positioned as the premium product and charges you extra for the dashing slope of the roof. For some, it won’t even matter that there is a price difference, and the X6M’s SUV ride height, ease of entry and exit, high seating position, dramatic styling and greater exclusivity are reason enough to preclude comparisons and cross-shopping, though the upcoming Mercedes-AMG GLE Coupe 63 will serve up another option in this niche soon enough.

Anyone who does have a vestige of concern for value will immediately see the additional practicality for the same performance and less cost as an unequivocal win for the X5M. While I, personally, can identify with those that favour the X6M for its styling and intangible flair, the X5M is a devastatingly quick and rewardingly responsive performance vehicle for its two tons of metal and glass, and can serve as family rocket or barnstormer plaything when the mood strikes, so its overall utility is undeniable in this matchup.

Warranty:
4 years/80,000 km; 4 years/80,000 km powertrain; 12 years/unlimited distance corrosion perforation; 4 years/unlimited distance roadside assistance
When you have two cars that are this similar and this nichey, there’s really no sense in covering every detail that we have already... 7/15/2015 10:30:06 AM
2015 BMW X5M Pricing: 2015 BMW X6M
Base Price $105,900 Base Price $108,200
Optional Equipment $13,100 (Premium Package: rear sunshades, ventilated M seats, blind spot detection, “Active Protection”, “Driving Assistant”, Surround View 360-degree parking cameras, satellite radio, alcantara roofliner, speed limit info – $7,500; ConnectedDrive with ARTTI package: real-time traffic info, internet, remote services – $500; smartphone integration – $600; full Merino leather – $4,500) Optional Equipment $13,000 (Carbon fibre trim – $500; smartphone integration – $600; night vision with pedestrian detection – $2,500; full Merino leather – $4,500; Bang & Olufsen sound system – $4,900)
A/C Tax $100 A/C Tax $100
Destination Fee $2,095 Destination Fee $2,095
Price as Tested $121,095 Price as Tested $123,295
Optional Equipment