For the new model to take off, it needs to match its predecessor's workmanlike qualities, while adding more driver involvement and a dash of panache.
To achieve success, the new Vectra will also have to get close to the Mondeo, the best driver's car in the sector, and jockey the Fleet News Award-winning Passat as the best built car in its class.
This is why we have chosen the Mondeo and Passat as the benchmarks on which to measure Vauxhall's new effort.
The Mondeo 2.0 TDCi 130 Ghia is a great drive with an excellent common rail diesel engine. At £18,245 on- the-road, it is the most expensive of the three test cars - £650 more than the £17,595 Vectra 2.2 DTi Elegance - but for company car drivers worried about their tax bills, the Ford's low carbon dioxide emissions should cancel out its price premium. The Passat 1.9 SE TDI PD 130 is marginally cheaper than the Mondeo at £17,960, but is a strong proposition with high driver appeal and solid residual values.
This test is something of a coup for Fleet News, because the paper is the first fleet title to receive a Vectra on test in the UK. And after a week in it, it is clear that the new Vectra truly is a car of our times.
It is positively Blairite: middle of the road, something for everyone, adequate solution rather than brilliant revolution.
It is not that this is a bad car. Far from it. The Vectra is a very fine fleet car and will do the job for which it was designed fantastically well. It is large and comfortable but without being particularly exciting in any one department, fulfilling Vauxhall's aim of creating a 'decathlete' car rather than a one event specialist.
The Mondeo is a treat to drive, but the Vectra is not far behind, which is apparently how Vauxhall planned it. However, the Vectra's 2.2-litre turbodiesel engine (not a common rail unit) tends to let it down in such polished company. Both the Passat and Mondeo engines are state-of-the-art and it shows in their much better fuel economy figures and lower CO2 emissions. The Vectra needs a common rail engine, which it gains next year when it gets the Fiat-based JTD unit.
Unfortunately, the 2.2 DTi means the Vectra suffers in terms of emissions. This will have little impact on company car driver wallets in this financial year, but when the emissions thresholds tighten, the tax cost gap between the Vectra and the Passat and Mondeo becomes more apparent.
At the residual value end of the equation, things are tight enough to make no difference, but the Passat is just about the best at holding its value after three years and 60,000 miles with CAP estimating it will retain 32% of its cost new.
The Mondeo (29%) and Vectra (31%) are not far behind, although the fact that the Vectra's engine may be less desirable in three years' time, in a world of common rail domination, may well end up counting against it. One thing is certain and that is the new Vectra seems to be a stronger resale proposition than the outgoing model.
As for specification, the Vectra has some extras the others do not get as standard. Its airbag count is high, with twin front airbags, front sidebags and roof-mounted side-curtains as standard. The Interactive Driving System, which controls skidding and understeer, is also the most advanced in class.
It is extremely difficult to pick a winner from these three because they are all so closely matched. The Vectra is the most comfortable, spacious and is a fantastic long distance tourer.
Despite costing extra in tax, the Vectra does not win any category outright, but competes strongly in all.
It might be one big compromise but it just squeezes in as my choice here as the one to go for, and will be the best of the three easily when it gets a better diesel engine with lower emissions.
Behind the wheel
I first got a lift in the new Vectra late last year, and a nice German Opel engineer with the job title 'PE-Chassisentwicklung' who drove me said he had tuned the chassis to be less responsive than the Ford Mondeo but sharper than the Renault Laguna.
He said the Vectra steering was set up so that the car would swap lanes quickly at high speed on a motorway with little body roll, and less twitchy steering than the Mondeo - a manoeuvre it would do thousands of times in its life.
But the best bit of all, for the claims of any manufacturer pre-launch are to be consumed with a pinch of salt, is that he is absolutely right. As a motorway cruiser the excellent ride, the straight tracking and calm steering of the Vectra put it top of the tree.
And it's good on twisty roads as well. The steering gives back enough feel to be able to hold it through a bend at speed, while understanding what is going on at the rubbery end, and its body roll is excellently contained.
For a combination of high speed motorway serenity and twisty road involvement it is a fine, well-sorted all round package that beats both the Mondeo and Passat.
It is not much of a looker in saloon guise though, which may be its Achilles heel, although the hatchback does look better.
Vauxhall kindly supplied this car to us nearly two months before the models start to fill Britain's roads, which makes it an extremely rare sight on UK roads and one which should generally turn a few heads.
Except that no one noticed it. In a week, four blokes in a Transit pointed at it, and two others commented to each other in a car park in Birmingham. It's not a head turner and in the world of volume fleet workhorses, does that matter?
The real weak point of the package is its 2.2-litre diesel engine. It makes a racket through first and second gears, even when warm, and although the vibration through the bulkhead has been damped as well as the Passat and Mondeo, noise and harshness have not subdued. At cruising speeds it is adequate, but it commits the cardinal fleet sin of having high CO2 emissions.
In a world full of common rail diesel competitors, the Vectra is being forced to struggle on with old school technology for the time being, much in the same way that Ford's Mondeo did at launch.
The Vectra interior is extremely sober, and apart from a few flimsy plasticky bits like the ashtray lid and blanked button panels, it is well put together.
One aspect where cost cutting seems to have taken hold is the rev and speed dials: can there be any more boring in the history of motoring than the flat grey panel with printed numbers on the Vectra?
RIDE and handling in the Vectra are on a par with the best in the upper-medium sector, the interior is spacious and well-equipped and the car has the most comfortable seats of any in the class.
The current diesel engine does let it down, but overall the new Vectra is a fine package.