Audi A4 2.0 TDI 150 ultra SEThe Audi A4 has been worrying the BMW 3 Series for 21 years now. From being a compact executive sector outsider, Audi now does battle with BMW and Mercedes-Benz to dominate the market for this type of car. These three brands alone sell four in every five compact execs globally.

The all-new Audi A4 is, rarely, just that: entirely all-new. It’s built on the new VW Group MLB evo platform – currently, only the new Q7 SUV also uses it – and follows the typical Audi story of being technologically leading-edge in every possible way.

Audi’s making a particularly big noise about its onboard tech. No car has this much connectivity as standard, it says, and the plethora of options brings in features that were standout in the A8 limousine sector just a year or two ago.

In base guise, it’s the lightest car in this sector. But the longest, widest and with the longest wheelbase, too – despite being all-steel, not part-aluminium (why is your aluminium so heavy, Jaguar?). It has an engine range that’s up to 25% more powerful and 21% less thirsty, and Benefit In Kind tax figures are down across the board.

Audi A4 2.0 TDI 150 ultra SE

With easily the best Cd aerodynamic drag factor in the sector (just 0.23 – thank features such as the ultra-crisp, ultra-hard-to-make bootlid edge pressing), you’d be forgiven for thinking the looks are all-new as well. As we’ve established though, they’re not.

The image above: can you split it from the old A4 at a glance? Audi’s evolutionary styling strikes again, which is why some are perhaps not as excited about the A4 as they should be. We are, though – because our early drive suggested Audi might well have a very good car indeed on its hands.

In a sector buoyed by a heavily revised 3 Series, all-new XE and the ever-present allure of Mercedes-Benz’s pretty C-Class, the Audi has a stern challenge on its hands. Fresh from docking in the UK and ahead of deliveries beginning on November 21, we tried out the volume 2.0-litre TDI on British roads to see just how good the new car is.

2015 Audi A4 2.0 TDI 150 Ultra SE: On the road

Audi A4 2.0 TDI 150 ultra SE

All-new platform, same familiar Audi feel – but with significant advances across the board. We tested the new A4 in volume 2.0-litre TDI SE guise, with sensibly-sized wheels and non-sport suspension. Unlike the older A4, there’s little to fault here, but a lot to like.

Rolling refinement is outstanding. The A4’s premium, luxury feel on the move is the first thing that strikes you, from the very low levels of road noise to the way bumps are absorbed without audible bangs. It’s a supple car too, with longer-travel suspension blotting out the lumps readily felt in the old one.

It’s stable at speed and the steering is accurate and settled, although if you up the speed on more undulating roads you’ll find the suspension becomes a bit choppier. It’s not as taut as a 3 Series though, or as wallowy as a C-Class can be, and it’s a good deal more able than its rather stolid predecessor.

Audi A4 2.0 TDI 150 ultra SE

The A4 isn’t much more exciting to steer through bends, though. As ever, Audi trades BMW and Jaguar-like thrills here for confident sophistication. The steering lacks feedback, it’s not the crispest on turn-in and you’re aware of body-roll when you start to get more energetic.

The 2.0-litre TDI engine, tested here in 150hp Ultra guise, is exceptionally quiet and smooth. Spinning sweetly, it lacks the clatter found in varying degrees in its rivals (the 3 Series is best, the C-Class is worst) and is mated to a vastly improved snick-snack gearchange.

It’s a familiar engine but this is perhaps its best installation yet. It ultimately lacks big-power shove at speed, but responds swiftly enough in town and maintains speed without fuss on the motorway. The 190hp gives you more, but you won’t feel short-changed here if you’re chasing low Benefit In Kind payments.

If you want dynamic involvement, go for a 3 or XE; what the A4 now does extremely well is out-Mercedes the C-Class for luxury car comfort. The ride has made a big step forward but it’s the sheer refinement throughout that really sets it apart. The A4 really will raise eyebrows here – and will make owners really feel like they’re getting a premium product.

2015 Audi A4 2.0 TDI 150 Ultra SE: On the inside

Audi A4 2.0 TDI 150 ultra SE

Audis are renowned for their superb interiors. But even by the brand’s standards, the new A4 is exceptional. Quality and craftsmanship easily surpass everything else in the sector; it’s better than many executive cars, not to mention some luxury models – that’s how good it is.

Meticulously assembled, the interior is more open-plan than the claustrophobic old car, with the slimline new dash taking cues from the TT’s wing-style design. You can have the TT’s virtual instrument cluster as an option, too. Audi’s really sweated over the choice of materials, from the full-length trim running across the dash to the brushed metal-effect plastic on the centre console.

Whether you look, touch and feel, there are treats. Buttons click nicely. Column stalks feel good. The dials are clear and the screen between them is super-high resolution. Audi’s MMI infotainment system has never been so easy to use. And the three-zone climate control system (standard on all models) has the digital clarity and tactility of an Apple Watch.

Audi A4 2.0 TDI 150 ultra SE

Connectivity is a major USP. All new A4s get Audi smartphone interface, which includes Apple CarPlay and Android Auto platforms. We tried CarPlay and it worked exceptionally well – it’s a fantastically appealing addition that may alone convince some to sign on the dotted line.

Because the smartphone interface links into your mobile’s mapping system, Audi doesn’t include sat nav on the standard SE. It doesn’t need to, it says, and we’d agree. Other extras are xenon headlights, rear parking sensors and cruise control – oh, and the 17-inch wheels Brits now consider a bare minimum.

In the rear, Audi matches the firm and supportively comfortable front seats with nicer chairs than any of its rivals. There’s plentiful space, too – enough for an adult to sit behind another. The boot is 480 litres and well-shaped. Needless to say, it’s trimmed in high-quality materials. Here and in other areas, Jaguar could learn a lot from Audi’s approach.

2015 Audi A4 2.0 TDI 150 Ultra SE: Running costs

Audi A4 2.0 TDI 150 ultra SE

Take that, BMW! Like Jaguar, Audi sells a 2.0-litre TDI A4 that dips under the 100g/km CO2 mark without resorting to EfficientDynamics trickery or limited trim options. You can even have it with 17-inch wheels rather than weedy 16s.

In 2.0-litre TDI 150 Ultra guise, it has a 74.3mpg average fuel economy figure, and Audi’s added some tech to help real-world economy; the stop-start system cuts in as you’re coasting to a halt, for example, rather than waiting for a compete stop. This means the engine is off more often than you may expect in traffic.

Retained values will be strong, albeit not as strong as the surprise leader in this sector – that’s the Jaguar XE. The 163hp 2.0-litre diesel SE holds on to 40% of its list price after three years; the test Audi pairs with the Mercedes-Benz C 200d SE on 39%, with the BMW 320d ED Plus (also surprisingly) trailing on 37%.

2015 Audi A4 2.0 TDI 150 Ultra SE: Verdict

Audi A4 2.0 TDI 150 ultra SE

Does the new Audi A4 now lead the compact premium saloon sector? No. The BMW 3 Series, in facelifted guise, still gets the nod from us. The A4 is close behind though, and leaps ahead of our other favourite, the Jaguar XE, in the final draw. That’s a mark of how much it has improved.

OK, it still doesn’t thrill behind the wheel. But it does satisfy, with its improved ride, smooth engine and, most of all, its refinement. It does what drivers buying this class of car expect, and makes them feel special. As it’s one of the best-value compact premiums on sale, this is a significant advantage.

It also has a truly outstanding interior, excellent connectivity and infotainment features, a plethora of optional tech and a fair haul of standard functionality included in the price. The exterior won’t turn any heads, but it will please and age well – and running costs will be sharply competitive too.

It’s hard to fault. The BMW is still our choice, but the A4’s strengths, and excellence in key areas, still make it a very strong alternative indeed.

2015 Audi A4 2.0 TDI 150 Ultra SE: Specifications

Model tested: Audi A4 2.0 TDI 150 Ultra SE

Engine: 2.0-litre four-cylinder turbodiesel

Gearbox: Six-speed manual

Price: £28,465

Power: 150hp

Torque: 236lb-ft

0-62mph: 8.9secs

Top speed: 130mph

Fuel economy: 74.3mpg

CO2 emissions: 99g/km