The core structure and vast majority of the engineering content was sourced from Honda but the vehicles were designed at the same time, with a small Rover team on site in Japan.

The 600's interior included wood and chrome trim, as well as relatively high equipment levels, although rear legroom was criticised by Parkers as rather constrained.

Production continued until the beginning of 1999, when it was replaced with the retro styled Rover 75, developed under BMW's stewardship.

However, shortly after the restructuring of ARG and its parent company British Leyland into the Rover Group, the plan was cancelled due to a lack of funds and as a stopgap, a facelifted and revised Montego (Project AR9) was released for the 1989 model year.

It would be aimed further upmarket than the Montego, competing more directly with the likes of the BMW 3 Series than with the Ford Mondeo, which was launched at around the same time.

Having been unveiled to the motoring press towards the end of 1992, the Rover 600 Series finally went on sale on 19 April 1993, two months before the new Accord on which it was based, although it had been well known within the motoring press that both cars were derived from the Japanese market Ascot Innova which had launched in March 1992, therefore the engineering and interior design elements of both the 600 and European-market Accord were essentially already in the public domain almost a year before their European launch.

The ti featured a set of 16" six spoke alloys with uprated suspension, 'Torsen' gearbox and a dark half leather interior.

The first revisions were in 1996, which included a slightly revised interior, with a padded front arm rest and separate rear head rests, all models, apart from the ti, had 15" wheels, high level brake light, new alarm and immobiliser system (the alarm changed from an infra red to a radio controlled handset and the ignition key became a 'transponder key', without which the immobiliser could not be disarmed), drink holders in the front doors, electric headlight adjuster and all models from Si specification upwards receive air conditioning and 15" alloys.

The 620ti also had uprated suspension, dark half leather upholstery, and a set of six spoke 16 inch alloy wheels.