Company car drivers have more reason than ever to look towards diesel, following the new emissions-based tax rules. Mazda now offers two common-rail, 2.0-litre units - one with 121bhp and the other offering 136bhp, both providing identical 43.5mpg fuel returns. We drove the more powerful unit. With 310Nm of torque available from 2,000rpm, it pulls hard and gives effortless overtaking ability and very little turbo lag. Refinement is excellent too, with minimal clatter in the cabin, and well damped vibrations.
The new estate body is sure to receive a good reception, too, whether buyers are looking for style or practicality. Its rear end is stylish with Lexus-look lamps that wrap around the body, following the wedge-like profile.
Despite this, the tailgate cuts deep into the rear bumper for a low loading height, and opens to reveal a usefully large luggage bay. The seats and belts fold flat at the pull of a lever offering a fully level, two-metre-long loading space with little in the way of intrusions from the suspension and wheel- arches. Lift the boot floor and there are more cubby holes - perfect for valuable items or muddy boots.
It's not only loads which can be accommodated easily. The seats are supportive and comfortable, while the dash is well laid out and dials are simple to read. With acres of space, the cabin is light and airy, while tall occupants won't feel the squeeze, with adequate legroom front and back.
The additional bodywork hasn't harmed the saloon's class-leading driving dynamics, either. The estate is great fun on the road, thanks to a competent chassis and ex-cellent brakes. Cornering is smooth and neutral, while the steering is positive, even if straight-ahead feels a little dead.
But the Mazda has a bigger problem. While the diesels are undeniably state-of-the art, they are let down on those all-important CO2 emissions. Most rivals have far cleaner engines and fall into the lowest 18 per cent tax band. The 6, on the other hand, produces a comparatively grimy 179g/km, which bumps it up two points to make it taxable at 20 per cent. That'll mean higher-rate earners will have to stump up around £200 more a year to drive the Mazda. And that could prove even more of a turn-off than those adverts.
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