Technology upgrades mean that adaptive LED headlights and cruise control are on the options list, as is a GPS-guided eight-speed automatic gearbox similar to that used by the Roll-Royce Wraith. BMW Connect is standard and comes with emergency assist. You can also add apps for live traffic reports, music streaming and a concierge service.
Right-hand drive versions still have slightly offset pedals, but otherwise the driving position remains faultless. There’s an oversupply of leg and head room, even if you're upwards of six feet tall, and that space is complemented by plenty of steering wheel reach.
This latest incarnation of the six-cylinder turbocharged engine has a touch more power – now 322bhp - and it’s as fabulous as ever. You can barely detect the signs of forced induction and it is delightfully smooth in its harmonics and power delivery. This wonderful linearity means it will pull from 1000rpm uphill in third as easily as it will eagerly blat around to its redline.
Our car had the six-speed manual gearbox, and although the theory is that it’s slightly slower than the automatic (0-62mph takes 5.1sec as opposed to 4.9sec), we think it's worth the trade in pace for the extra interaction. This is thanks to the lovely weighting and precision of the change, along with pedals that enable you to heel and toe with ease.
This was almost a requirement around our snaking Portuguese test route that was also a decent test for the M135i’s chassis. On the approach to a corner the brakes feel positive and progressive, and as you ease off them and begin turning in, the front end bites, which gives immediate confidence.
Mid-corner there’s a little lean before the body settles, and then it’s a case of exploiting that predictable engine map and the car’s innate traction to fire it out and on to the next kink. It's a process that you'll want to repeat over and over again.
However, the variable-ratio steering, despite being firmer than that of the standard 1 Series, is still a touch too light and urgent with its initial response, and there’s precious little feedback through the wheel.
Furthermore, hit a bump mid-bend with the M135i’s suspension under load and it has a disconcerting tendency to give a little skip sideways. This trait didn't cause any real dramas, but it sowed the mental seed that at full tilt it isn’t quite as tied down as it first appears.
That said, for a car with this level of performance, on the optional adaptive dampers the ride is relatively forgiving. Even stepping up the challenge by aiming at bigger potholes failed to make it feel crashy. Indeed, the only thing that was any bother was a slightly bouncy high-speed ride.