But that, of course, is the point of this car. It’s big enough to seat five in absolute comfort, and even those banished to the back will find a lot more space than usual once installed.
They’ll need flexible bodies, though, because getting past the forward edge of the wheelarch requires dexterous effort.
The boot is bigger than you’ll find behind the third row of seats some seven-seaters, but for truly usable space you can drop both rows to uncover 2121 litres of finely upholstered goods tray.
Fine upholstery there and everywhere else is a pleasingly unmissable feature of the X7, this being the latest of BMW’s luxury range whose stablemates include the 7 and 8 Series, all identified under the Bayerische Motoren Werke label.
Such is the surface area of seat trim that the choice of material and trim can have a dramatic effect on the cabin ambience, as can the option of the vast glass roof, which part-opens.
The impact of the X7’s interior will be as nothing compared to the business of conducting it down a road if you have never driven a vehicle of this scale before. You’re sitting high and the rear window is a long way off, but it’s the X7’s width and the initial feeling of bulk that can intimidate. Even on American Interstates the lane-keeping assistance will be kept busy if you don’t concentrate on herding it between lanes.
That’s not because it’s a wanderer, but simply because it occupies a sizeable chunk of said lane. This is a car in which lane-keeping is a real benefit, as is its semi-autonomous ability to edge ahead in traffic jams unprompted, by harnessing the radar-governed cruise control.
Motorways are likely to be a primary habitat for X7s, and it’s hard to imagine anyone flinging one about with BMW sports cars in mind. Despite this, BMW’s chassis engineers have aimed to deliver a driver’s car, its X5 roots helping.
The scope for bold cornering in Florida, this test drive’s ultimate destination, is limited but a quiet roundabout revealed a fair bit of well-controlled roll in comfort, less of the same in sport and more gainliness than you might expect of from a vehicle the size of a decently voluminous van. Its air suspension can turn the ride a bit bouncy over deeper dips, but you can slice through long sweepers with a verve that Starbucks-swilling back-benchers will find distinctly unamusing.
The 40i X7 is not hugely quick, which is no surprise given its bulk. But it’s less hefty on its wheels than you might expect with 2320kg to cart, all all-out assault on 62mph completed in 6.1sec. The inline-six is whirringly smooth at low to middling revs, forays towards the red danger paint turning it a little strained-sounding. The eight-speed transmission ensures you rarely stray there, though, unless you paddle or nail the throttle, especially as it downshifts willingly.