A NOT so small saloon and a very hot hatch are the latest additions to the Audi line up.

Both the new A3 saloon and the S3 hatchback sit on the acclaimed MQB modular platform and in the case of the saloon it has produced remarkable results.

It is the 30 completely new model Audi has launched in the past 12 years and it finds itself in a niche of its own.

Priced from £24,275 the A3 saloon is alone in the compact premium sector as a car with a boot.

The market is dominated by hatchbacks and all that comes close to the new Audi are coupes from Mercedes and BMW and the slightly larger Volvo S60.

But 40 years ago saloons were the in thing and in a good old fashioned way the new A3 is a breath of fresh air.

In terms of price it sits below the A4 saloon and when it comes to general handling it's a step ahead.

It looks smart and sleek, well proportioned and inside - as with all versions of the A3 - it's nicely decked out.

The saloon is some six inches longer than the A3 hatchback but lower and the boot at 425 litres can carry almost ten per cent more. Like for like the saloon costs £550 more than the hatchback A3.

For convenience the boot lid rises automatically as soon as it's unlatched and with folding rear seats the cargo space rises to 880 litres.

Leg space in the back is adequate rather than generous but head room throughout is satisfactory for all but the tallest.

Making the transition from hatch to saloon has not simply been a case of sticking a boot on the back and the underpinnings of the car are entirely individual.

On the road the A3 saloon is not only surefooted but remarkably supple delivering a smooth but responsive drive.

The handling is spot on and initially there's a choice of three engines - 1.4 and 1.8-litre petrol and a two-litre diesel.

All are lively and the 1.4 features Audi's cylinder on demand technology which cuts out two of the four cylinders under low power demand pushing average fuel consumption up to a claimed 60.1mpg with emissions of 109g/km.

In everyday driving expect to achieve around 50 to the gallon yet with a top speed of 135mph and a 0 to 60 time of 8.4 seconds the performance from the 140ps turbo engine suits the car to a tee.

The 1.4 engine is mated to a seven speed auto box with paddle shifters for sportier manual changes and stop/start is a standard feature. It costs from £24,305 in Sport trim and £26,455 in higher grade S line trim which extras such as xenon headlamps, 18-inch alloys and some sporty trim.

Surprisingly, it is the diesel which is the cheapest of the saloon range which, given its greater economy makes it an attractive option.

We managed to average 58 to the gallon and although that's still shy of the official 68.9mpg it is a creditable figure for a saloon in this class. Emissions are down to 107g/km and the engine has plenty of pull giving it an acceleration time of 8.7 seconds topping out at 137mph.

Although heavier and available only with a six speed manual box, it rides equally as well as the 1.4 version and all of the saloons come with Audi's multi-mode Drive Select set up which enables the car to be switched into a variety of settings ranging from sport to eco.

As with other versions of the A3 the saloon can be fitted with a range of communications equipment which includes Bluetooth, Google Mapping and an ultra quick 4G Internet link.

A 1.8-litre turbo petrol automatic is also available priced from £25,995 and this is the quickest of the bunch with a 0 to 60 time of 7.3 seconds and a claimed average mpg figure of 50.4 with emissions of 129g/km.

Later in the year other engines will be added to the saloon line up including a 1.6-litre diesel while early in 2014 a high performance S3 will arrive featuring Audi's new two-litre TFSI engine which generates 300ps.

This engine is making its debut in the S3 hatch and five door Sportback and it is incredibly potent.

All versions of the S3 have quattro all wheel drive and tipping the scales at less than 1.4 tonnes it is lighter than its mainstream rivals such as the Mercedes A45 AMG and the BMW M135.

Priced from £32,120 for the three door it is also marginally cheaper and with a six speed manual gearbox it is good for 0 to 60 in 5.2 seconds topping out at a limited 155mph.

Despite the performance the fuel economy is a claimed 40.4mpg with a CO2 figure of 162g/km and realistically it is surprisingly frugal. We averaged almost 33 to the gallon from a spirited drive.

However the driving experience is full on and the S3 leaves you with no doubt about its lively credentials. Compared to the previous generation the engine has 40 horsepower more and it shows.

Sporty kit includes black brake callipers, a roof spoiler and a rear diffuser plus four exhausts while inside there's a flat bottomed steering wheel, stainless steel pedals and quality leather upholstery embossed with S3 logos. Even the instruments - which include a turbo boost gauge in the rev counter - have their own special touch and are finished in grey.

The S3 is also available with the S tronic six speed auto box and although slightly quicker - 0 to 60 is down to 4.8 seconds - it's also thirstier with an official mpg rating of 40.9. It's priced from £32,740.