Subaru's pioneer is a great estate

It is a chunkier version of the Legacy estate, with the same flat or boxer engine and all-wheel-drive. This is the fourth version of the model that Subaru says pioneered "crossover" . A crossover marries an estate car with a sports utility 4x4. Discuss terminology by all means. To me, the Outback is nothing more than an estate car with all-wheel drive.

The diesel version is my pick of several dozen new cars I drove in 2009. I liked its all-purpose nature. It is smart, quick enough, economical and it can go anywhere I need to get. Throughout its repertoire it was so pleasant to use, with one glitch (see panel below).

I have talked to other motoring writers about the diesel Outback and they all felt the same way: loved it, except for that glitch – which may be a question of lack of familiarity.

There are lots of rivals for the "crossover" crown but Subaru pitches in with this bigger and roomier Outback that, with a hearty two-litre diesel engine, summarises all I need in a car any day of the year, any weather, any road.

The four-cylinder flat engine, two pairs of cylinders lying either side of a common crankshaft, punches out a smooth but characterful 148bhp and 258lb ft of flexi-torque (the best-known flat or boxer engine maker is Porsche, which has used one since it evolved from the 1930s Volkswagen).

Subaru likes the flat engine because it has a lower centre of gravity than an upright cylinder stack. It is also robust and has a throaty "thwump". Until recently it only had petrol versions, tending to be thirsty. The diesel, though, addresses economy while still having the charming "flat" mannerisms.

The official mileage forecast is 44mpg, with a reasonably clean 167g/km of CO2, thanks to improvements to this unique engine since its launch in 2008. The 0-62mph acceleration time is 9.7 seconds, with a maximum 120mph in sixth gear (if you want an automatic you'll need to buy the thirstier 2.5 petrol or the gulping 3.6).

I enjoyed this car so much. It was easier to drive than the rival Volvo XC60 which preceded it on test and preferable to the sporting Alfa Romeo 159 which followed it.

At 26,295 it does cost quite a lump for the standard SE model, yet this is well equipped with a self-levelling rear end on double wishbone suspension, partly reclining rear seats with a handy latch inside the tailgate to fold them away and voice-activated Bluetooth phone connection.

Electronic stability control is standard, as is climate control. Navigation with a reversing camera and pushbutton, keyless ignition and entry is an additional 2,000. On the 2.0 diesel, the four-wheel drive has a centre differential with a viscous limited slip. On dry roads, the power is shared equally front and rear. When one pair of wheels loses grip, the differential transfers power to the wheels with grip. In practice, it means you should get through.

The 2.5i model has a more sophisticated 4x4 system which constantly monitors the car's behaviour and front/rear torque distribution, making adjustments according to sudden changes on the road surface. During normal driving, the torque distribution which achieves the best fuel economy is used. The 3.6R is 45:55 biased towards the rear to suit the handling dynamics of this rapid version.

Europeans are mostly buying the diesel Outback. You should reckon on 40mpg in mixed driving, rather less with stop-start journeys, a bit more on long-distance runs at sensible speeds.

Overall, a winner on my score card, with good road manners and middle-market persona. Rear passengers have more leg room than in a normal limousine. This is a great estate car.

On the road

Motor: Horizontally opposed four cylinder 1,998cc diesel giving 150ps and 258lb-ft.

Pace: 120mph tops and 0-62mph in 9.7 seconds.

Economy: Subaru quotes 36.7mpg urban, 50.4mpg extra urban and 44.1mpg overall with 167g/km of CO2.

Price: One model in SE trim at 26,745 with climate control and skid prevention, 17in alloys with Yokohama all-weather tyres.

Overall: One car to fit all purposes and seasons.

Except: It has a zany locking system which meant passengers could not always open their doors quickly to get out. The flat-four 167ps 2.5 petrol model is the same price, fitted as standard with a CVT automatic gearbox. It is a convenient package but high mileage motorists will pay at pumps. The official figures are 33.6mpg combined and 194g/km CO2. The 0-62mph time is 10.4 seconds. The 3.6R is the performance model. The flat-six engine delivers 260ps. It can reach 140mph and 0-62mph in 7.5 seconds. It costs 33,995. Combined mpg is 28.2mpg and it emits 232g/km CO2.