Audi's A3 hatchback kick-started the premium, compact hatchback segment with the introduction of the first generation car 20 years ago, says Auto Express. But now in its third generation, it's facing stiff competition.

As well as rival Mercedes Benz offering a hatchback with its remodelled A-Class, BMW is also in the race with its rear-wheel drive 1 Series.

Audi updated the A3 earlier this year to offer customers a facelifted model with new styling, engines, and technologies. Here's what you get.

Body styles and shapes

The A3 is available in more than just hatchback form, and in a number of different body styles and models.

The most conventional and popular cars are the two hatchback versions. The A3 hatch is a three door and one of the most ubiquitous models (there's also a five door version). Called the Sportback, it's a slightly larger car with 2.8ins more legroom and a different rear profile with more headroom. You'll also get a bigger boot – 380-litres compared to 365.

If a hatchback doesn't appeal, a compact four-door saloon version can be bought. Its traditional three box shape makes it the longest version of the car at 14.7ft in length, but the lower, sporty roofline means headroom is slightly compromised. The car does, however, have the biggest bootspace – 425-litres.

The final body shape turns the A3 from a family hatchback into a small four seat convertible. The A4 cabriolet is the most expensive version, though it's the least spacious with its roof in place and a small 320-litre boot. The boot's capacity drops to 285-litres for cars with a Quattro all-wheel-drive system, making it the most impractical.

Engines

Depending on the trim level, the A3 is available with a large selection of engines.

The smallest option, which can only be specced on the A3 hatch or Sportback, is a 1.0-litre TFSI three-cylinder petrol delivering 114bhp, a claimed 62.8mpg and CO2 figures of 104g/km, making it cheap to tax. Two other petrol options are available on the standard A3 - a 1.4-litre TFSI with 148bhp, delivering virtually the same co2 and efficiency scores.

A 2.0-litre TFSI is the most powerful petrol you can buy before verging into S3 territory. It produces 187bhp, 50.4mpg and 129g/km CO2 and can be specced with a Quattro all-wheel drive system.

The three diesels begin with a 1.6 TDI with 109bhp, although its 74.3mpg rating makes it the most efficient choice, while the 99g/km CO2 figure means it is exempt from road tax.

Two 2.0-litre TDIs sit above it, one with 148bhp and the other with 182bhp. The less powerful version is front-wheel drive as standard but can be selected with all-wheel drive if you're willing to incur a big efficiency hit. The most powerful diesel is Quattro as standard.

S3 models come with a turbocharged 2.0-litre petrol engine producing 306bhp. It's a potent machine and while the least efficient choice, it's easily the fastest – 0-62mph takes just 4.8secs.

However, the now discontinued RS3 Quattro can still be found on dealership forecourts. It uses a turbocharged five-cylinder engine with 362bhp. Evo says it's a "formidable cross-country machine".

A final engine option, the A3 E-Tron, will be available soon. It's a hybrid-powered version of the Sportback, making use of the 1.4-litre TFSI petrol engine mated to a six-speed S-Tronic gearbox and an electric motor.

Very few details have been revealed, but the older model comes with headline figures of 201bhp, 0-62mph in 7.6secs, 37g/km CO2, a range of 580 miles and 31 miles on electric power only.

Interior

The A3 carries over Audi's established reputation for interior quality and CarBuyer believes it is one of the best interiors in its class.

Build quality is high. Controls are made using robust, premium materials and the cockpit layout mirrors the horizontal design style found on bigger Audis.

It's a nice place to be and CarBuyer says it's comfortable, too – the standard seats are perfectly positioned with plenty of adjustability while the likes of heated or sportier bucket seats can also be specced.

Cars get a thin 7ins infotainment screen that pops out of the dashboard, but Audi also offers a second option plucked straight from many of its larger cars. The marque's excellent virtual cockpit system replaces the manual dials behind the wheel with a large, 12.3ins display. It's best used with satellite navigation to display large maps clearly and right in front of the driver.

Safety

Auto Express says safety is one of the A3's trump cards and the car's scores in Euro NCAP tests are very impressive, drawing particular attention to the 95 per cent score achieved in the adult occupant protection category.

The A3 comes an impressive range of safety and convenience features, although a lot of the big-car tech is reserved for the optional extras list on entry level cars.

For instance, there's optional radar-controlled cruise control, which consistently maintains a set distance from the car in front, as well as lane-keep assist and Audi's "Pre Sense" autonomous braking technology, which is handy around cities. Optional Emergency Assist is one of the most extensive additions and can steadily bring the car to a complete halt if it detects no activity from the driver after repeated warnings.

A self-parking system can be specced to make tight spots much easier, as can systems for hazard warnings when pulling out or reversing into cross traffic.

Prices

The A3 hatch in SE trim with the three cylinder 1.0-litre engine starts at £19,365, while the Sportback kicks off at £19,985.

If you're after the saloon version, you'll have to fork out £24,235, although it isn't available with the 1.0-litre engine and entry level consists of the 148bhp 1.4-litre TFSI. It's the same story with the cabriolet at £26,875.

The cheapest diesel option is more expensive than its petrol counterpart and S versions, at £32,330 for the hatch, cost significantly more. There are similarly raised prices for other body styles.

Reviews

The Daily Telegraph gives the A3 five stars out of five and declares it is no longer just a Volkswagen Golf wearing a posh frock.

Despite the mid-life refresh only introducing very subtle design changes inside and out, the A3's cabin remains a sharply designed, premium cockpit, says the paper, but the new tech additions are what really steal the show.

Audi's rollout of its Virtual Cockpit display across nearly all of its range is proving popular and now the A3 can have it fitted, the Telegraph feels it's easy to see why the hatchback has an upmarket, tech-focussed, premium image. It recommends stumping up the £450 needed to fit the system.

Engine choices are smooth, continues the paper, and while the A3 is more of a settled car to drive compared to the thrills on offer from the likes of the BMW 1 Series, it's still fun and a "fabulous all-rounder".

As for which one to go for, Auto Express singles out the 1.6-litre TDI in Sport trim - it's also the cheapest one to run, thanks to a claimed 74mpg and sub 100g/km CO2 figures making it road tax exempt.

As standard, you'll get 17ins alloy wheels, Xenon headlamps, sport seats, cruise control and sat nav.

As for the A3 saloon, What Car? rates it as a "superb compact executive car" and scores it four stars out of five.

Again, the classy cabin taken from the A3 hatch is said to be one of the car's key features, with the site saying the interior quality is such that despite this being a small car – it's much shorter than saloon rivals the Mercedes C-Class, BMW 3-Series, and even the Audi A4 – it's one that buyers of full-sized executive vehicles may find an enticing proposition.

"Throw in rock-solid resale values, attractive PCP rates, and efficient engines that bring down company car tax rates, and you have a serious contender in the executive class," adds What? Car.

On the road, the entry level 1.4-litre TFSI engine is "punchy" and the site mentions how the 148bhp power unit has cylinder de-activation technology, so it can shut down two of its cylinders when not needed in order to save fuel.

What? Car add that it's possible to make the A3 saloon a comfortable cruiser by removing the sports suspension.

It's still an exciting and composed car to drive, it concludes, and "you'd need to spend a lot on a BMW 3 Series to get anything more agile or involving to drive".