Price and EquipmentTHERE’S a line in the sand between Alpina and BMW despite both starting out on the same production line.

Buyers seek out Alpina because of its exclusivity and its more compliant ride and power delivery, justifying the added expense by turning to the high resale value.

The Alpina B4 is based on components from the BMW 440i and M4, taking its body and some cabin and suspension components and creating a coupe that looks similar, yet is very different to drive.

It is closer in philosophy to the BMW M4 Coupe, though there’s a lot to tell them apart.

Picking the Alpina from a car park of 4 Series Coupes isn’t easy but train spotters will pick the distinctive 20-spoke alloy wheels and body pin striping, while inside there is a metal dashboard plaque stamped with the production number.

Upholstery choice and trim items are of a higher quality – for example, all leather is the premium-grade Merino – and there’s a sense that the hand-crafted workmanship is better than the predominantly machine-driven BMW components. But in most cases, you’d be splitting hairs.

Put the 440i, M4 and the B4 side-by-side and the Alpina sits lower and has a fatter stance at the front, exaggerated by its 20-inch wheels – not the other Bavarian’s 19-inch rims – and stretched to 265mm wide at the rear.

Inside, the leather is embossed and the dash plaque is obvious – perhaps too much so. The 440i is comparatively plain but is still drop-dead gorgeous.

Technically, all Alpina current models have high-torque engines, are always torque-converter automatics and focus on the buyer’s need for a luxurious cabin.

It eschews BMW’s run-flat tyres, preferring to engineer the suspension much firmer than the donor BMW and then allow the tyres to do the hard yards by absorbing more road shock.

The engines are not the same, though the eight-speed automatic is shared with the 440i but Alpina adds some fine tuning to better extract the extra torque and send it to the mechanical rear differential, a replacement for the 440i’s electronic diff. The M4, by comparison, has a seven-speed dual-clutch transmission.

Then there’s the price. The 440i coupe automatic is $99,900 plus on-road costs while the B4 coupe (there’s also a convertible) is $160,900 plus costs. The M4 coupe is $149,900 plus costs and offers quicker acceleration but a more brutal ride and handling package better suited to enthusiasts.

For the extra $61,000 (440i) and $11,000 (M4) you lose a handful of safety and convenience items – self-parking steering, lane departure warning with passive steer, forward collision warning among them – and only have a two-year warranty against the BMW’s three years.

But you do get that deliciously smooth engine, neck-cricking acceleration, an arguably smoother ride and a sunroof. Bonus.

InteriorThis is a car aimed at the well-heeled, discretionary buyer wanting an instant hit of visual opulence. Well, the Alpina B4 isn’t precisely that but its rich leather cabin does look a few steps up from the already impressive 440i.

The leather is the best Merino – no, nothing to do with the sheep just a premium-grade cow leather – with beautiful stitching and embossing. The leather looks thick yet feels as soft as a fine-ply suede.

Alcantara is used for the headliner and pillar trim, with piano-black panelling used for the dashboard fascia and door trim with leather used to crown the instrument binnacle.

It shares the basic instrument panel with the 440i/M4 but the gauges have much simpler graphics are backed by unique deep-blue faces.

The centre console is dominated by a large screen that is the medium for the satellite navigation, 360-degree camera, functions for the ventilation, vehicle operations, audio, connectivity – including access to apps – and telephone.

Operations are controlled by a twist-and-press dial edged by quick reference switches for frequently-used features such as the radio and maps. A rack of numbered buttons allows owners to set their own favourites.

The basic dashboard is clean and simple like the 4 Series range, with electric park brake, lidded centre bin, cupholders and the joystick-like gearshifter.

Aside from the different steering wheel with its Alpina crest in the centre, the B4 gets steering-wheel gear shifters. But unlike the 440i that has floating paddles, the Alpine has protruding buttons integrated into the back of the wheel spokes. It keeps the look clean but the small buttons are not as easy to locate and operate as paddles.

The front seats are softer than the donor but retain excellent side support to uphold Alpina’s promise of sports performance with comfort. Heating is standard for the front seats.

There’s no change over the 4 Series coupe to the capacity of the accommodation – with room in the rear for two adults on short trips – though getting in and out of the back seat requires some dexterity.

Boot space is one of the best in its class at 445 litres, exceeding the Mercedes-Benz C-Class Coupe at 400 litres and only beaten by the 455 litres of the Audi (see rivals).

But its liberal cargo capacity comes at the cost of not carrying a spare wheel, instead providing a repair kit. Given the Alpina doesn’t have the 4 Series’ run-flat tyres, the lack of a spare could become a problem away from urban areas.

Engine and transmissionSo you’ve read down to this point and figured out you can save a substantial $61,000 by buying a BMW 440i coupe off the floor and an $11,000 saving for the M4 and the Alpina will pretty much be the same in all departments.

And this is the point where I tell you that it simply is not the same.

The philosophy behind Alpina is to make fast cars work more efficiently and, in doing so, be easier cars to drive. It probably irks BMW that there’s a second stream of competitive cars coming off the same production line.

But they are designed for different buyers and in the Alpina’s case, a driver with more money and possibly a greater awareness of what’s under a car’s skin.

Alpina don’t use the latest BMW 440i 3.0-litre in-line single-turbocharged engine as a starting point. They actually use the M4 engine block that has a different bore and stroke – resulting in a 2976cc capacity instead of the 440i at 2998cc – and lots of internal differences.

It gets two turbochargers and power climbs to 301kW at 6240rpm, up from the 440i at 240kW at 5500rpm. The accent is on torque with the B4 punching 600Nm at 3000-4000rpm compared with the 440i at 450Nm at 1380-5000rpm. The M4 hits even harder at 317kW/550Nm.

It’s enough to sprint the Alpina to 100km/h from rest in a slick 4.2 seconds, 0.8 seconds better than the 440i and only 0.1 seconds slower than the M4.

There is a stark difference in the delivery. The B4 is smooth with almost seamless upchanges through the box, similar to the 440i but with more locomotive urge so the engine always feels at the top of its torque curve as it picks up the next ratio.

The M4 is the enraged bull at the gate, using its brazen dual-clutch shift to ram through the next cog.

But don’t write the B4 off just yet. Though subtle and docile around town, it will roar and scream when shown an open road and transfer into an especially responsive engine that revs hard towards the red line.

The more mature, less aggressive style of the Alpine is responsible for a reasonable 7.6 litres per 100 kilometre economy, a bit thirstier than the 440i (6.8L/100km) and yet less than the M4’s 8.3L/100km. The B4 is the only one of this trio of BMWs to seek 98RON fuel.

Ride and handlingThe platform is identical to the 4 Series Coupe though the Alpine dispenses with the electronic differential and uses a mechanical limited slip differential (LSD), giving better traction without artificially braking offside wheels.

It shares the 440i’s electronic dampers and the “drive select” modes that run from Sport+ through to Sport, Normal and Economy. The wheels are similarly asymmetrical – bigger at the rear – but have 20-inch rim sizes, up from the 440i and M4 at 19-inch, and unlike the 440i, are not run-flat tyres.

Alpina states that this gives a softer ride that is reigned in by a slightly firmer setting for the dampers. The end result is that on most surfaces, the B4 is smoother and more compliant in its ride, so that occupants would judge it to be more comfortable.

But the critical factor is that the B4 can be pushed equally as hard into corners as the M4 with a better ability to absorb any mid-corner bitumen imperfections. Would the M4 be quicker – yes. But the B4 wouldn’t be far behind and would give a more supple ride.

The B4 gives away a 191kg weight penalty to the M4’s 1499kg – the 440i is 1517kg – which curbs some of the engine’s enthusiasm. Where’s the weight? Mainly it is in the cabin with the full suite of leather, the extra weight of the LSD, bigger wheels and the two turbochargers.

But despite this, it’s only one tenth of a second slower than the M4, reflective of the aim to maximise the engine’s torque output as a way to ensure performance. Respect.

Safety and servicingThe Alpina sits beneath the BMW umbrella for service and warranty, sharing ownership costs and the conditional service intervals. Service costs can be pre-paid for various periods in the future.

The Alpina isn’t listed with an expected resale value after three years but as an exclusive car – and depending on finding a buyer – is presumed to be higher than the BMW 440i coupe’s 51 per cent.

Safety equipment is good but many rivals – and indeed, the 440i donor – are better. Alpina comes standard with six airbags, blind-spot monitor, front and rear park sensors, a 360-degree camera, LED headlights with washers and cornering function, tyre pressure monitor and head-up display.

All these are on the 440i but the BMW adds emergency warning lights, lane departure warning with passive steering, automated park assist and forward collision warning.

Verdict The subtlety of this car is its biggest surprise. You expect unbridled performance yet this is a very mature iron fist in the proverbial velvet glove.

As such it is far more flexible and civilised than its rivals.

It is also demonstrably more comfortably than the competition and will even outmatch the donor BMW 440i for ride comfort. It is just a superbly executed car that has its main problem being its attributes lost on researchers who compare data, not driver feel.

An extremely liveable – and potentially resale rich – family car for the quiet minority.

RivalsAudi RS5 from $157,226 plus on-road costs
The slinky coupe version of a platform that has launched a thousand Audi models gets injected with a 331kW/430Nm 4.2-litre V8 that despite lacking turbocharging will sling the two-door to 100km/h in only 4.5 seconds. The RS5 gets a seven-speed dual-couch transmission driving all wheels and Audi claims 10.5L/100km of 98RON fuel.

Standard kit includes sat-nav, 10-speaker audio with digital radio, 19-inch alloys and six airbags. The RS5, almost identical to the Alpine in length which makes it the smallest car here, has the largest boot at 455 litres. The warranty is three years or unlimited distance and the resale value after three years is the best here at 53 per cent.

Lexus RC F from $138,240 plus on-road costs
Japan strikes at Europe’s heartland with a 5.0-litre normally-aspirated V8 rated at 351kW/530Nm driving the rear wheels through an eight-speed torque-converter automatic. It claims 10.9L/100km. Boost space is 366 litres and the coupe is the heaviest here, though still runs 0-100km/h to equal the Audi at 4.5 seconds. Features include autonomous emergency braking, sat-nav. sunroof and eight airbags. The warranty is four years or 100,000km. Resale is 50 per cent.

Mercedes-AMG C63 S Coupe from $162,115 plus on-road costs
The blistering quick C63 Coupe rushes the 100km/h sprint in the quickest time here at 3.9 seconds and yet – not at the same time – will get an average of 8.7L/100km. The power plant is a bi-turbo 4.0-litre V8 cranking 375kW/700Nm and powers the rear wheels through a seven-speed dual-clutch automatic. Standard equipment includes sat-nav, sunroof, automated steering for parking, ceramic-composite brake rotors, AEB, a 13-speaker audio system and 19-inch front wheels and 20-inch at the back. Boot space is 400 litres. The warranty is three years or unlimited distance. Resale is 51 per cent.