THE Mondeo is Ford's replacement for the popular Sierra - a car that came to be trusted by families and people who do a lot of driving as a good-value motor car, smart enough for middle managers, big enough for hauling children, and reliable. And the new car has to be significantly better than its predecessor to win over customers. Also, the stakes have been raised by the arrival of some excellent Japanese cars since the Sierra first hit the road. If the Mondeo was anything less than exceptional, Ford stood to lose both money and standing. Fortunately, for Ford, the Mondeo is, indeed, exceptional. It comes without the blandness that afflicts cars attempting to please all of the people all of the time. Touted as the first ''Ford World Car'' - a car that combines all the qualities needed to make it saleable throughout the world - the Mondeo was designed as a compromise. Mondeo's success can be put down to its superb chassis and looks, and an engine that, although not as outstanding as the car's other features, is good enough to put the Ford at the top. It is distinctly European in behaviour. The Mondeo displays the one quality which keeps some drivers faithful to European cars - good chassis dynamics. The Mondeo handles and rides with a crispness and firm confidence that sets the standard. New steering and suspension systems give exceptional feel and ride control and the body has a solid feel that suggests the build quality is unusually high. The ride is firm in typical German style, with tight suspension that keeps body roll in check, pot-holes are swallowed without discomfort or rattles and, where the Sierra used to feel vague and under-damped when pushed hard, the Mondeo is assured. The automatic gearbox moves between ratios cleanly and quietly especially at town speeds, but parking is made difficult because the nose of the car is out of sight from the cabin. Drivers accustomed to the very light steering commonly found in modern cars will find the Mondeo's steering heavy at first - more effort is needed to turn the steering wheel. The brakes, fitted with an ABS anti-lock system as standard, are firm and progressive and give the driver confidence. They bring the car to a halt with a gentle push of the peddle. Other controls also share this weighty, quality feel. While the exterior of the car is smart but plain, the cabin is modern and impressive. The electrically powered driver's seat adjustment works well. The steering wheel can also be moved up or down. The dash and door mouldings curve elegantly and the interior is free of squeaks and rattles. Only the hard plastic of some of the fittings spoils what is otherwise a very comfortable interior. Little road noise penetrates into the cabin, but accelerating hard makes the four-cylinder engine loud enough to become a nuisance. The Mondeo is quick when the need arises. Ford has yet to gain the large market share in Hong Kong it enjoys in Europe. But, with the Mondeo, local Ford dealer Wallace Harper has a product that should attract new custom.