Road Test: Volkswagen Golf 2.0 GT TDI 5dr

VW's diesel hot hatch is infuriatingly difficult to criticise. It'll do 67.3mpg and 0-62mph in 7.5secs. It emits 109g/km of CO2. It's slick and Volkswagen-y inside. The driving experience is beguilingly refined, and not just for a high-powered diesel. There's plenty of space. And the styling has just the right amount of swagger.

Of course, it's also better than the old one. The 2.0-litre 4cyl turbo's output has increased by 13bhp, torque has grown by 22lb ft and weight has dropped by 27kg. That's trimmed the 0-62mph dash by 0.6 of a second and dropped emissions by 30g/km CO2.

That said, unlike the petrol, there's no Performance Pack power upgrade. But the hefty torque reserves make it feel properly rapid in the mid range. It's a responsive thing, too, and there's slightly more breadth to the rev range - it'll climb up to 4,000rpm before getting out of breath.

If you hit the Sport button, it'll even pipe in some pleasing (albeit synthetic) hot-hatch whumps and growls. And in Normal mode - which, let's face it, is where it'll be most of the time - it's tremendously quiet and composed.

VW has done a ton of chassis work to help polish the GTD's dynamic refinement, too. The suspension has been lowered and stiffened, there's the company's convincing XDS+ traction control (pinches the inside front wheel to stop wheelspin, and the inside rear to pivot it into corners), the GTI's quick two-turns-between-locks steering rack, and you get bigger brakes.

It suffers a bit from the GTI's risk-averseness through corners, especially if you go for a DSG auto over the six-speed manual - it alienates you rather more than you'd like for a performance car. But it's a confident, wieldy thing. Just don't expect the full-on sauciness of a thoroughbred hot hatch.

Inside, it's also a little more sober than its warmer contemporaries. But there are enough nods to the GTI pedigree to make it feel special: wantonly retro tartan seats, dimpled golf-ball gearknob, sports wheel and a special GTD instrument cluster.

But there's a fly in the ointment. It costs £25,285. The full-house petrol GTI will set you back only £560 more. You can get a Seat Leon FR diesel, which shares its MQB platform, does 65.7mpg, 0-62mph in 7.5 seconds and 112g/km CO2 for £22,375. Which makes our only criticism of the GTD... the availability of a cheaper one.