Subaru is guaranteeing customers exceptional value from the final-edition versions of its iconic Impreza 2.5 WRX saloon and Sports Wagon.

Called GB270, the last-of-the-line current Impreza offers around £7,600 in extra equipment for the saloon and just under £7,000 for the Sports Wagon.

Both models cost £22,995 on-the-road – only £2,898 and £1,898 more than the standard Impreza WRX saloon and Sports Wagon respectively.

Named after Rally GB – Subaru’s most successful WRC stage – and the 270 PS the Prodrive-uprated engine produces, the GB270 models can be ordered from July 10 with first deliveries planned for September 1.

Numbers will be strictly limited to 300 for the Impreza GB270 saloon and 100 for the Sports Wagon.

Both models benefit from the 270 PS Prodrive Performance Pack which boosts power by 40 PS and torque by a staggering 74 lb ft to 310 lb ft.

The result is a 0-60 mph time reduced from 5.9 to 5.3 seconds and a 0-100 mph time of 13.9 instead of 14.4 seconds. Mid-range response is substantially improved.

Other shared features include a lowered spring kit, ‘quickshift’ gearchange, special carpet mats, MOMO ‘Air-Race’ gear knob, larger-diameter 18x7.5ins GT1 alloy wheels and GB270 exterior badging and individually numbered interior plaque.

Specific to the Impreza GB270 saloon are a WRC-style rear spoiler, stainless-steel mesh front grille, STI front lip spoiler and silver-finished alloy wheels.

Helping the GB270 Sports Wagon stand out is a rear waist spoiler, front and rear aero splash guards, rear privacy glass, black stainless-steel mesh front grille and gloss-black alloy wheels.

In addition, both models will be available with an optional ICE pack consisting of a Clarion SatNav and iPod adaptor and Bluetooth ’phone kit for £1,750.

Other extra-cost upgrades include a GB270-branded leather or Alcantara/leather interior for £1,400 or £1,600 respectively and privacy glass window tinting for the saloon at £405 (all prices include VAT).

A totally new 5-door Impreza will be launched in the autumn in 1.5 and 2.0 litre naturally-aspirated versions only. The turbocharged STI returns in the spring.