After months (and months) of advance publicity, Opel's 3-Series challenger debuts at the London Motor Show.

The Insignia is Opel's (or, in the UK, Vauxhall's) push into the mid-size segment following the path of the smaller Astra and Corsa.

Available in sedan format, as is the norm for this size car, there's also a coupé version that doesn’t cut back on interior space — it offers three centimetres more knee room than the Vectra — while benefiting aerodynamics. The Cd figure is 0.27, bringing with it benefits in fuel consumption, cabin refinement and performance. Both body variants have identical 4830mm length and share the same wheelbase of 2737mm.

The new car hits the UK at the end of 2008 with a line-up of five engines that come with either manual or automatic six-speed transmissions. The three petrol engines range from a four-cylinder 103kW unit to a 191kW V6. The two new direct-injection turbo-diesels developed exclusively for the Insignia are both 2.0-litre capacity, but offer different power and torque outputs of either 95kW/300Nm or 117kW/350Nm. An ecoFLEX variant with lower fuel consumption and CO2 emissions will be added in the near future.

The Insignia also features technological innovations. The new "Front Camera System" can both read and memorise road signs as well as alert drivers if they unintentionally veer off the road. The "Hot Shot" heated washer fluid takes some of the hassle out of winter driving. And the improved "Adaptive Forward Lighting" (AFL) also increases driving safety.

Featuring all new chassis architecture, the Insignia is offered from the start with front-wheel and all-wheel drive. The "Adaptive 4X4" system’s proactive, instantaneous torque distribution improves driving stability, traction and dynamics.

In the all-wheel drive Insignia, the "FlexRide" chassis system with its "Adaptive Stability Technology" helps the car continually adjust to prevailing road conditions and allows drivers to select settings to match their mood. "FlexRide" is also available in the front-wheel drive version.

The Insignia hatchback offers a luggage compartment volume of 500 to 1465 litres, and includes a ski-hatch opening in the rear seat-back for load-through storage.