Sector: Lower-medium Price: £24,305 Fuel: 60.1 CO2: 109g/km

Possibly the biggest compliment I can give to the A3 saloon fitted with Audi’s Cylinder on Demand (CoD) technology is that I didn’t once notice the car had it.

It works so well that you never feel the engine shut down two of its four cylinders in order to save fuel. And you certainly don’t feel them chime in again when you need to speed up. In fact, you only really notice the CoD technology through the information screen between the speedo and rev counter in the instrument binnacle.

The system has been operating on peripheral Audi models for a few years, but now it is really in the mainstream – available in both A1 and A3 models. It works simply enough by shutting two cylinders when the engine is operating under a light throttle loading, for instance when cruising on the motorway. But if you need extra power, the idling two cylinders will join back into the action in just 13 milliseconds.

As well as being effective on the road, the CoD tech makes for an interesting conundrum for company car drivers… the A3 saloon in our test car’s guise offers 60.1mpg combined fuel economy and CO2 emissions of 109g/km. While a comparable A3 diesel (1.6 TDI Sport S tronic) delivers 72.4mpg and 102g/km, it is the petrol Audi which is more tax efficient thanks to its lower list price (£24,305 v £24,405) and lower benefit-in-kind tax banding (14% plays 16%).

As a result, a 40% tax-payer in the petrol A3 saloon will pay £113 a month in company car tax, compared with £130 in the diesel. In fact, the more you look at the A3 saloon, the more sense it makes. It is certainly the most handsome saloon in the lower-medium sector (granted, that’s not difficult) and its size is not that far removed from its more expensive A4 stablemate, being just 245mm shorter and 11mm less tall.

If outright economy and space are not high priorities, the A3 saloon is worth investigating, especially in petrol guise with Cylinder on Demand technology – this is a refreshing alternative to diesel, but without having to forego the economy benefits that come with it.