Mazda has sky-high hopes of its new 6 range taking off in the fleet market again, says motoring editor Andy Russell.

I've been to some interesting – and uninteresting – press briefings about new cars but sitting inside Concorde at Scotland's National Museum of Flight at East Fortune Airfield, East Lothian, comparing Mazda's new 6 range to the ground-breaking supersonic airliner seemed a flight of fancy.

Here the Mazda marketing men were highlighting in a humerous, but honest, way how just as air travel was taken to new heights when Concorde 001 was rolled out in 1967 – the year Mazda launched in the UK – so the third-generation Mazda6 will set a benchmark. It too evolves a tried-and-tested form of transport, in this case the car, with its engineering-led, lightweight approach to better performance while optimising economy and emissions.

Mazda UK managing director Jeremy Thomson said the 6 was most important car Mazda had ever made. Originally launched in 2002, it saw a change in Mazda's fortunes, making a big impact with fleets and private buyers. Now new Skyactiv technology, honing conventional engines, gearboxes and technology to get the best output from the least input to puts the new 6 up there with the class-leaders for low emissions and high economy and performance, was the next stage of journey.

It will revive the Mazda6's fortunes after sales tailed off recently against cleaner, greener rivals in this highly-competitive sector.

A bit over the top, you might think, but the Mazda6 is a huge leap forward.

The new 6 is a real looker, hardly surprising when it remains true to the styling cues of the Shinari and Takeri concepts. Like the CX-5 sport utility vehicle, which debuted Skyactiv technology, the 6 shares the eye-catching Kodo – Soul of Motion – design cues of bold, sweeping curves that make the 6 look so athletic. It has real kerbside appeal which is is so important in the cut-and-thrust fleet market and, judging by the approving nod of one BMW driver we passed, the looks do the business.

Power comes from the new range of 2.0-litre petrol and 2.2-litre turbo diesel engines, rated at 145 and 165PS and 150 and 175PS respectively, not small, weedy 'eco' engines which makes the figures more impressive.

The 6 sees the debut new i-Eloop – Mazda's brake energy regeneration system which uses a fast-charging electric capacitor to power the car's electric systems as much as possible instead of the engine so saving fuel.

Diesels will be big sellers, accounting for 85pc of the fleet market and 70pc of private sales –no wonder given the 150PS version in the manual saloon has best-in-class emissions of 108g/km and combined MPG of 67.3.

Having driven both diesels, I preferred the 150PS one which gives little away in terms of real-world performance but is better on fuel ane emissions and also available in all six trim levels – SE, SE-L and Sport each with Nav versions.

This flexible diesel offers the best of both worlds combining willing low-down pull with top-end urgency where it revs happily without feeling strained.

Only the more powerful petrol engine was available at launch and, compared to the diesel, it needs to be worked to feel lively but, to be honest, does not really match the promise of a 165 horsepower. It is also the only engine not available with a six-speed automatic option.

The Mazda6 has always been an entertaining drive and the new model does not disappoint. It feels agile and sporty on country roads with good body control through corners and precise, accurate, well-weighted steering.

The ride on SE and SE-L models with 17in alloy wheels is compliant and comfortable over a variety of road surfaces but Sport models' 19in alloys with lower-profile tyres may look good but do the ride no favours – it's over-sensitive and unsettled with far too much tyre noise and feedback into the cabin.

The Mazda6 is now offered only in saloon and Tourer estate which are expected to account for 60 and 40pc of sales respectively – the CX-5 is now seen as the hatchback alternative. Both offer plenty of loadspace with the saloon's long 483-litre boot not far short of the Tourer's 506-litre cargo bay. Both have 60/40 split rear seats backs which can be dropped from the boot and fold flat. And there's plenty of leg and headroom, front and back.

The driving position has all the adjustment to tailor it to the driver's needs and the dashboard is clearly laid out with user-friendly controls. The cabin is well finished with a quality feel high up but lower plastics are more durable than delightful.

Class-leading specifications add to the 6's all-round appeal while an automatic braking system on SE-L and Sport have cut insurance rates by up to six groups.

Mazda says the 6 is back with a vengeance in the fleet market and also more compelling to retail customers. Its confidence is justified.