There is no tougher automotive segment in the world than the compact executive class, which has long since been ruled over by the BMW 3 Series and Audi A4. And the Lexus IS does run its German rivals close, clearly out-pointing them in some areas.

Most impressive is the Lexus's almost uncanny level of refinement, on smooth roads at least. The petrol engines are some of the smoothest units we've experienced, combining whisper-quiet performance with a wonderfully silken power delivery - best experienced through the optional, ultra-smooth six-speed automatic gearbox.

Dynamics are good, with the IS putting on a reasonable display of enthusiasm over a more demanding country road - but over-firm suspension tends to lead to a crashy, uncomfortable ride on bigger bumps. The petrol-powered IS250 puts in a strong performance - while still turning in decent fuel consumption figures. The turbodiesel engine in the IS220d is well-mannered, although not a match for the BMW 320d on performance or refinement.

Perhaps most boldly, Lexus has the BMW M3 in its sights with the V8-powered IS-F. It certainly has the pace - and brakes - to trouble BMW's flagship 3-series, but the ride verges on being too firm to live with. The engine really comes into its own at higher revs, with a second air intake meaning that the noise goes from enjoyable to gloriously addictive.

For those that want the looks but not the running costs of the F, there is the option to go for the F Sport trim package. This brings the 18-inch alloys, subtle aesthetic additions inside and out and little F badges. The ride is naturally a little compromised by the bigger wheels, but it is still no worse than the S Line or M Sport trim levels offered by Audi and BMW.

The IS's cabin is well-finished and practical thanks to well-chosen, tough materials. It's hard not to be disappointed by the dashboard design, though - especially the old-fashioned looking digital displays for the stereo and climate control. Rear seat space is relatively tight and the boot can only offer class average levels of space.

Competitive pricing and excellent standard equipment make the IS a good option for private buyers, even if the emissions mean that anyone having to pay company car taxation will edge towards its German rivals.