SAAB'S 9-5 isn't really hampered by the 2.0-litre turbo engine fitted to its entry level model - even in the heavier estate model.

The 2.0-litre 110kW engine was introduced here to maintain a competitive pricing advantage in the 9-5 range without compromising too much the big Saab's reputation for brisk performance.

And it manages this admirably.

The 2.0-litre 9-5 (it misses out on the S, SE and Griffin appellations used in the more upmarket models) proves to be an impressive performer, smoother than the 2.3-litre versions yet not suffering from any significant power loss.

2.0-litre Saab 9-5 buyers aren't asked to be especially frugal in their thinking in terms of equipment and fittings either.

Alloy wheels aren't part of the deal, but all the worthwhile 9-5 stuff is climate-control air-conditioning, heated front seats, headlight washer-wiper system, cruise control, CD/radio/cassette seven-speaker sound system and (manual) multi-adjustable front seats remain integral parts of the deal.

And, of course, it gets all the 9-5 safety gear such as anti-lock brakes (with electronic brake force distribution), driver and passenger airbags as well as sidebags, and Saab's clever anti-whiplash front seats.

So there is very little missing in this entry-level version of the impressive Swede.

Realistically, most people won't pick the drop in engine capacity from 2.3 litres. And what the engine does lose in torque and outright power, it tends to compensate with a delightfully smooth engine that seems to benefit more from the use of twin balance shafts than does the bigger 2.3-litre.

Similar to the bigger engine, the 2.0-litre develops its torque low in the rpm range, helping the car respond quickly at low road speeds.

About the only difference with the bigger engine is the urgency of the response. For a given effect, the accelerator has to be squeezed a little harder and a little longer.

Apart from that, the story is exactly the same as the 2.3-litre version.

With the Volvo V70 wagon - shortly to be replaced by the more expensive V80 - its clear target, the Saab pushes the argument of sleeker looks and more refined road behaviour as its main competitive advantages. These may be diluted by the V80, although the new Volvo's chassis is based on the current V70 that has never been renowned for its smoothness and sophistication.

But the Saab's big deficit is the lack of a third row seat.

The company cites occupant safety as the reason for forgoing this very marketable extra.

Saab says that because the extra seat in a station wagon configuration is in the rear crush zone it cannot provide a safe environment for passengers and, so far, no-one else has come up with conclusive evidence the Swedish company is incorrect.

That said, there is no doubt many buyers needing the extra capacity who may have considered a Saab will look elsewhere.

The focus on safety issues is consistent with Saab's philosophy. The 9-5 scores highly in terms of passenger protection, rating a best-ever score in Euro NCAP testing.

The car does not get the extra, inflatable tubular bags fitted by BMW but it does get side airbags built into the seats as well as those "active" anti-whiplash front head restraints which play a part in making the passenger environment as safe as possible.

The Saab picks up the nicely balanced suspension used on the 9-5 sedan, beefed up by slightly tauter settings that subtly improve the Estate's response to steering wheel inputs without really compromising ride quality.

The 2.0-litre 9-5 Estate provides a big, comfortable cabin with generous load space and excellent all-round legroom.

And the seats are excellent - everything you would expect in a prestige contender.

On the road, the 9-5 Estate is impressive because it never really feels or sounds like a station wagon.

The cabin is muted even at high cruising speeds and there is little or none of the harmonic resonating that besets even the most competently engineered wagon.

The rear cargo area, which is accommodating but not quite as large as Saab would have us believe, is well shaped and generally free of protrusions. It also has an unusual but effective solid cargo cover, contributing to the sedan-like ambience, and offers an optional - and handy - slide-out rear floor capable of carrying up to 200kg.

In all, the 9-5 Estate is among the very best of station wagons when it comes to driving enjoyment and it also has potential as a silk-gloved workhorse.

For the money, it offers unquestioned style and grace, plus the appeal of being perceived as something outside the mainstream.

And it proves that a properly designed 2.0-litre turbo four can be perfectly comfortable in a big, luxury station wagon.