LOWER, wider and wearing a different suit cut to the 3 Series, the BMW 4 Series in two and four-door Gran Coupe guises look the goods for press-ahead driving.

Starting our sampling of the new range in the $68,900 plus costs 420i Gran Coupe, the spritely spirit of the small turbocharged 135kW/270Nm 2.0-litre four-pot is quickly apparent, spinning quickly and smoothly toward the redline with minimal harshness.

An absence of turbo lag and somewhat swift progress isn't difficult to achieve for the 1425kg entry-level machine, which now sits on an adaptively damped chassis with 18-inch wheels as standard.

Ride quality as a result is decent on the dimpled roads of country Victoria, which are traversed at a quick clip.

Even switching to Sport mode does not detract markedly from the ride quality, although the tightening of the chassis is apparent.

Steering is on the light side in comfort mode but weights up with purpose in the sportier modes the ability to split drivetrain and chassis functions within Sport mode is a little more complex than the Individual mode offered by some of its opposition.

While some of the trim colours on the test vehicles are a little different and not to all tastes, the leather seating offers good adjustability and support, if not plush levels of cushioning reach and rake adjustable steering allows the driver to get a sporting driving position down behind the wheel.

But the driver does still have to adapt to the odd demeanour of the gear selector, which doesn't always do as the driver would like, particularly on a quick three-point turn where neutral isn't ideal.

Moving to the other end of the spectrum and the extra punch on offer from the 3.0-litre turbo in the $99,900 440i is considerable.

Jumping from 135kW to 240kW, with 270Nm rising to 450Nm, drops the 0-100km/h by 2.5 seconds and raises the thirst by a claimed 1.0 litre per 100km.

Sporting a far sharper pricetag also does plenty to improve the appeal of the flagship, which features a M three-spoke steering wheel with the chunky leather rim to direct the variable-ratio sport steering.

The 440i does bite into corners with some enthusiasm and – like the 420i – the flagship has nicely-weighted steering and composed road manners.

A degrading road surface does show up the lower-profile run-flat rubber on bigger wheels as less sympathetic to the rear end, relaying more of the road ruts and bumps through to the cabin.

A brief saunter through the sodden countryside in the Convertible version of the 440i resulted in a slightly less favourable impression, with the athletic feel of the Coupe dulled by the drop-top’s extra weight – the flagship weighs 1555kg in coupe guise but 1770kg with the removable roof.

Even a brief test in the rain with the roof down showed the neck vents of the $117,900 Convertible worked, as did the aerodynamics of the exterior to keep buffeting to a minimum after the roof conversion was completed at 20km/h.

The boot space remains compromised at a maximum of 370 litres, dropping to 220 litres with the top packed in, but if the roofless mode is required sporadically and security is high on your priorities list, the folding hard-top is a reasonable all-rounder.

BMW said the outgoing 428i was the most popular variant of the 4 Series line-up, regardless of body style, and its replacement seems likely to carry on that mantle, if perhaps not quite to the same extent given the sharper pricing on the top-spec model.

The $79,900 430i Coupe sits as firmly but with some compliance on the road, as do its siblings, but it feels a little more lithe than the more powerful six-cylinder 440i.

Firing drive to the rear is the more potent 185kW/350Nm tune of the 2.0-litre turbo four-pot and it's lower weight (1510kg) works wonders with the nose of the vehicle, resulting in a coupe that has delivers more than enough power and torque for effortless commuting.

The lower kerb weight doesn’t do it any harm when the mood for amusement overcomes the driver, as it is a little more nimble.

When firing along the roads less travelled, the more composed and lithe nature of the 430i works in its favour, as does the less extreme wheel/tyre package when it comes to a ride quality that’s a little less edgy than the flagship.

While the roads on the launch drive were saturated, the adaptive chassis set-ups offered good grip, rarely awakening the stability control despite some provocation.

BMW has given the 4 Series the features, powerplant and, critically, the pricetags to take on its primary opposition from Audi (which is set to renew its A5 range – which has coupe, convertible and four-door body styles) and Mercedes-Benz among others. It’s going to be an interesting fight.