There comes a point when you realise that a fairly new model has caught on. I reached it on a recent motorway trip, when I was passed by a Vauxhall Vectra, then a minute or so later passed by another, and after what seemed like a 60-second gap found another one wafting past.This went on, honestly, for about ten minutes in a row. I came to the conclusion that either there was a Vauxhall dealer convention just up the road, or I was in the middle of some kind of automotive Groundhog Day, or - yes - that the latest Vectra has really arrived.Our test car was an SXi, billed as the first model on the "sport" ladder, although I think that may be pushing things a little. Certainly it had details like 16" alloy wheels, front fog lamps, sports front seats, a chromed gear lever knob, a metal-effect centre console and steering wheel inserts, and a chunky leather-rimmed steering wheel which provided a good handful, but there's nothing particularly sporty about the way it acts on the road.The next-step-up SRi has 17" alloys, a sports chassis set-up, rear spoiler, stainless steel tailpipe and so on, and that's more like it.However, the SXi with the 2.2-litre petrol engine is a very smooth operator, just the job for a long motorway run. It has, naturally, all the passenger room front and rear which characterises the Vectra and demonstrates how the Omega is showing its age, as well as loads of luggage room, with a space-saver steel wheel under the floor.There's an unusually wide rear-view mirror, while the lights and wiper stalks have the self-centring (or, rather, self-horizontalising) action of all the Vectras. Our SXi came with a few options including pull-up sunblinds for each rear side window, and a load-restraining net in the boot.Vauxhall offers plenty of other options, from rain sensor wipers and a good front-and-rear park warning system with different notes at each end, to a tyre pressure monitor, self-levelling rear suspension and various kinds of sound and navigation systems.In that general regard, I wonder just how long it would take to make a serious perusal of the paperwork that comes with a Vectra. The owner's handbook runs to 256 pages, and the audio manual is even thicker.Inside, the SXi is like the other Vectra models in having what seems to me to be a rather awkward angle where the strip of fascia trim meets the front door trim. All the controls are convenient to use, the instrumentation is OK but fairly plain, and there's an unusually large roof-light area beside the sunglasses holder.As with some Vectras of the previous generation - and there's no real point in criticising the car for not being something other than the design team intended - the SXi doesn't mind dashing along back roads, but it's really most at home in commuting journeys and/or long-distance cruising, where its comfort and quietness levels are just what's required.The 2.2-litre all-aluminium engine is one of Vauxhall's efficient if screaming-capitals ECOTEC units, and it lets the SXi perform in a lively enough way. This model is a little lighter than the similarly-engined SRi, which probably explains why it's geared at 22.8mph per 1000rpm in fifth rather than the SRi's 23.1mph, for what are said to be exactly the same performance, economy and CO2 emissions figures.Like most of the variants in the Vectra catalogue, the SXi costs the same with either four-door saloon or five-door hatchback bodywork, the latter being the only kind available in the higher-up 2.2 SRi specification.Altogether, the 2.2 SXi shows not just how much roomier but also how much more refined the latest Vauxhall is than its predecessor, and how much more work went into making sure it wasn't simply a mild modernisation project, the big snag about the original move to Vectra from Cavalier.Second opinion: Don't ask how, but I got lumbered with having to drive the entire distance between Sussex and the west Highlands of Scotland twice in consecutive days during my time with the Vectra. The ideal test for a repmobile, you might have thought, and indeed the Vectra is a quiet and, in most respects, comfortable cruiser. But the ride quality is lousy. The car thuds downwards and floats back up again on uneven road surfaces, and since you get the effect at both ends there's also a terrible pitching action as the front and rear take turns in being utterly confused by whatever bump they have been presented with. And this is the car they said has been tuned specially for UK roads? Pshaw. (For the record, the M40 just past the Brackley interchange is by some margin the most Vectra-hostile piece of tarmac I have yet encountered.) David Finlay. Engine 2198cc, 4 cylinders Power 145bhp Transmission 5-speed manual Fuel/CO2 32.8mpg / 206g/km Acceleration 0-60mph: 9.2 seconds Top speed 134mph Price £16,220 Details correct at publication date