If you’re a self-confessed BMW M car fanatic, you’ll probably know that the 3.0-litre straight-six under this X4’s bonnet is a true M division-fettled engine that shares very little with the 3.0-litre engine in the cheaper X4 M40i. It churns out 503bhp – exactly the same as the Alfa Romeo Stelvio Quadrifoglio and Mercedes-AMG GLC 63S coupé .
However, and slightly disappointingly, the X4 M’s engine is the least savage of all these. It doesn’t have the bombastic soundtrack of the GLC, nor does it offer quite the alert accelerator response of the Stelvio. It still makes the X4 M mighty fast, though, pulling from low in the rev range all the way up to its 7200rpm redline, and its six-cylinder howl is anything but unpleasant.
The eight-speed automatic gearbox fitted to the X4 M Competition hesitates very slightly when you go to pull away, but it's still much better than the frustrating F-Pace SVR in this respect. Once on the move, it shuffles gears almost imperceptibly when left in its default Efficiency mode.
We actually wish there was more ferocity to the gearshifts in the more aggressive driving modes; this would better suit the engine’s crazy power output. Still, using the launch control function, the X4 M will dismiss the 0-62mph sprint in 4.1sec, a time broadly in line with what the competition can achieve.
As well as adjusting the speed of shifts and the weight of the steering, you can also change the stiffness of the X4 M’s suspension. Unfortunately, even in the most comfortable setting, it fidgets almost continuously over craggy roads and you’re bounced around in your seat over larger intrusions. If you want a sports SUV that keeps one eye on comfort, you’d be better off with a Macan or Stelvio Quadrifoglio.
The X4 M isn’t the quietest of cruisers, either. Its door mirrors whip up considerable wind noise on the motorway, and the standard-fit 21in wheels kick up quite a racket as their wide tyres pummel the road surface. The Macan is a generally more refined sports SUV.
The M car fanatics we acknowledged earlier may willingly put these flaws aside for the promise of sublime handling, but there’s mixed news on this front, too. Despite BMW’s claims that it should feel just like a performance saloon, the X4 M just can’t conceal its two-tonne weight and higher centre of gravity. Yes, it does resist leaning over well for something this tall, but it never feels as agile as a Stelvio in the bends, or as involving.
Sure, the steering is precise and well weighted (as long as you avoid Sport Plus mode) but you don’t get a huge amount of feedback filtering up to your fingertips. Once settled into a fast corner, though, the X4 M can carry a surprising amount of speed through it thanks to having loads of grip.