This fifth-generation Legacy offers a 3.2-inch longer wheelbase that adds nearly 4 inches of rear seat legroom, 9 percent increased passenger volume, and a whopping 30 percent increase in trunk space, when compared with pre-2010 models.But it's only 1.4 inches longer overall, thanks to shorter overhangs.For 2010, the Legacy has been widened by 3.6 inches and its chassis stiffened by 39 percent for ride, handling and stability.

Powertrains include a new 3.6-liter six-cylinder engine, a new turbocharged double-overhead-cam four-cylinder, and a revised 2.5-liter single-overhead cam engine.

The body has been restyled as well, though nothing radical.More pronounced fender flares reflect today's styling, and there's a nice new grille with a bolder chrome trademark wing.Most of the many improvements are under the skin.

We found the 2010 Legacy wonderfully comfortable, with roomy seats front and rear, and high-quality interior trim.We particularly liked the perforated leather on the Limited models.These aren't luxury cars necessarily, but they are premium cars in terms of the quality of materials and the engineering that goes into them.The trunk on this sedan is quite large.

We found the 2010 Subaru Legacy 2.5i, the base model, effortless to drive.The transmission works automatically, with nothing to do but put it in Drive and go; the CVT gets good fuel economy.The 2.5GT offers sportier performance with its turbocharged engine, while the six-cylinder 3.6R has strong low-rpm power for excellent drivability.

All of them offer good handling, benefits of the all-wheel drive, a low center of gravity and nicely tuned suspensions.

The 2.5i Premium ($20,995) adds a 10-way power driver's seat, alloy wheels and leather-wrapped steering wheel.The 2.5i Limited ($24,995) comes standard with leather-trimmed upholstery, a four-way adjustable power passenger seat, dual-zone climate control, nine-speaker harman-kardon 440-watt audio system, 17-inch alloy wheels, all-weather package, and the CVT.

The 2.5GT Premium ($27,995) uses the redesigned 265-hp turbocharged engine with six-speed gearbox, and 18-inch alloy wheels with wide profile tires.The all-weather package is standard.Moonroof ($995), harman kardon audio ($995), and Bluetooth ($399) are optional, with iPod and USB connection an available accessory.The 2.5GT Limited ($29,995) adds perforated leather upholstery in ivory and off-black, the four-way power passenger seat, dual-zone climate control, the sound system and Bluetooth.A voice navigation system with backup camera is optional.

The 3.6R ($24,995) comes with the new 3.6-liter six-cylinder engine and five-speed automatic transmission with paddle shifters, along with 17-inch alloy wheels with all-season tires.The 3.6R Premium ($25,995) adds 10-way power driver's seat, all-weather package, and leather-wrapped steering wheel.The 3.6R Limited ($27,995) adds leather, the four-way power passenger seat, dual-zone climate control, harman-kardon sound system, and Bluetooth, with navigation optional.

Safety equipment on all models includes front and front side airbags with side curtain airbags, ABS with Brake Assist, Vehicle Dynamics Control with traction control, and tire pressure monitor.

In front, the Subaru badge of stars is ringed by a new chrome grille whose lower edge is squared off.Character lines arc from the grille and form power bulges on the hood and taper upward to the A-pillar.The profile is sleeker, even though it's 3.2 inches taller than before.The roofline is coupe-like, even with an increased greenhouse.The wider chassis spreads the front track by 2.7 inches and rear track by 3.3 inches, giving the Legacy a noticeably wider stance.

But the styling element that is most noticeable is the aggressive wheel arches and edged flares, enhanced by handsome alloy wheels.Subaru has always offered good-looking wheels, although they are followers in the edgy fender flare department; the Nissan Altima coming to mind as the first sedan to embrace this look, and now pretty much everyone is there.Interestingly, it was the 2006 Mitsubishi Endeavor SUV that started it all with its Geo-Mechanical look.

There's a short rear deck (deceptively covering the large trunk), with squared-off rear valances (smooth and not boxy), part of the standard aero package, giving an impression of size.However, even though the front overhang is less than before, the new Legacy still looks a bit odd in profile (when you study it), slightly platypus-like, with its long rounded nose.

On the 2.5GT, a prominent hood scoop sucks in air and tunnels it to the turbocharger intercooler.Along with the 18-inch wheels with wide-profile tires and twin-tip exhaust, it's clear that the GT means business.

New unseen engineering for 2010: The new rigid chassis contributes to the silence of the interior.It's a full reinforced cage of high-strength steel, heavier, although the new Legacy is still only 49 pounds heavier than before, thanks to weight-saving in other areas.There are also new fluid engine mounts, which add to the exceptional smoothness for a four-cylinder car.

More head room, leg room, hip room, shoulder room, front and rear.Exception: less front leg room, which is a practical place to borrow some leg room for the rear, because there's still 43 inches in front, and now 37.8 inches in rear, an increase of 3.9 inches over the pre-2010 Legacy.Overall, there is an increase in passenger volume to 103 cubic feet (from 93.5 in the previous car).

We found the front bucket seats wonderfully comfortable.The rear seats, especially in perforated leather, fit as nicely as the fronts, with a new scalloped seatback that gives more knee room.

The trunk has been blown up to 14.7 cubic feet, large enough for four sets of golf clubs.Gas strut supports, no intrusion into trunk space: quality detail, for such an affordable midsize car.Typical for Subaru.

The new Legacy is very quiet inside (especially the six-cylinder), thanks to a number of things, such as framed door glass and double sealing of all four doors.The rear doors are 15 inches wider (with double beams providing more strength against impact), for easier entry and exit.

The interior materials are higher quality all around.The center console offers more space thanks to a new standard electric parking brake, which includes the Hill Holder system that now lasts until the car accelerates, not just a couple seconds.The four-gauge instrument panel is clean and stylish, with a multi-information display standard.The controls on the center stack are all well done.The electronically controlled HVAC system is all new, with powerful and quiet air conditioning and optional dual zone control.The three-spoke steering wheel isn't as handsome as the rest of the interior, although the optional leather wrap is nice.The ambient lighting for the console is pleasant.Visibility in all directions is good.

We tested both transmissions in the base Legacy 2.5i, which we chose as our test model because that's the biggest seller.We like the Legacy 2.5i with the optional Continuously Variable Transmission.Called a CVT, this transmission works automatically, with nothing to do but put it in Drive and go.It makes driving effortless and gets 4 more miles per gallon than the six-speed manual gearbox.The CVT model comes with paddle shifters on the steering wheel allowing the driver to shift into different ratios.Called Lineartronic, and driven by a chain (actually more of a metal belt) for durability, this compact CVT is Subaru's first CVT in recent years, but the company was an early leader in the technology, making CVTs some 20 years ago.

All three models have Subaru's Symmetrical All-Wheel Drive, but they are different systems.The manual transmission uses continuous awd with a viscous-coupling locking center differential to distribute power 50-50 at all times; the 2.5i with CVT uses Active Torque Split awd that electronically varies the front-rear distribution; and the 3.6R model uses Variable Torque Distribution which sends more power to the rear wheels but adjusts to the front when it senses the need.

The 2.5-liter four-cylinder engine has been revised with new pistons and ports, and a new cooling system.This boxer-4 produces 170 horsepower and 170 pound-feet of torque, which is about the same as before, but the torque peaks a bit lower at 4000 rpm.We challenged the engine and CVT during a day of driving in the Pacific Northwest, and only hot-rodders will need more acceleration than this 30-mpg sophisticated $21,000 midsize car offers.

The 2.5GT comes with a new six-speed manual gearbox.The 265-hp turbocharged engine gains 20 horsepower over the '09 model, but more importantly, because of a new larger turbocharger with a better location, lower and nearer to the exhaust, the 258 pound-feet of torque is all available from 2000 to 5000 rpm.And there's no lag.The new 2.5GT cuts 1.6 seconds off the previous 0 to 60 acceleration time, now at 5.9 seconds.

The new chassis features a front subframe with a cradle that lowers the engine even more.Subarus already handle well because of the inherent excellent weight distribution offered by the front-mounted boxer engine, and now that handling and responsiveness gets even better.With standard all-wheel drive, there isn't a better design for stability on the road, among sedans.

The suspension is all new, if not revolutionary: MacPherson struts in front with double wishbones in rear, and larger anti-roll bars than before.The wider track is part of the package for more stability, 2.7 inches wider in front and 3.3 inches in rear.That's a lot.

The steering ratio has been quickened on the 2010 Legacy to 14.5:1 on all models, and this is a positive change that you can definitely feel.We did our best on some back roads on a Puget Sound island, and the quickness put a smile on our face, even with the modest 2.5i.

There's also a redesigned brake booster that results in an improvement in response, which Subaru says is 20 percent.The brakes feel good and inspire confidence.

The 3.6R gets an engine displacement increased by 20 percent over the previous 3.0R.Its power and smoothness make it feel like a much more expensive car.The base 3.6R with cloth interior is only $25,000, and for another $3000 you get lovely perforated leather, the nine-speaker harman-kardon sound system, and a couple other luxury things.The 3.6R offers the same 265 horsepower as the hot-rod 2.5GT, delivered more smoothly with a sweet 5-speed automatic transmission, while getting 18 to 25 mpg on regular fuel.Don't forget it's all-wheel drive.Although maybe one reason it feels so right is because the Variable Torque Distribution leans toward rear-wheel drive.Quite a sedan, for less than 30 grand.

There doesn't appear to be an area of performance that Subaru has missed improving.More responsive power, better transmissions, redesigned suspension, wider track, more rigid chassis, quicker steering ratio, more responsive brakes.Kudos, we say.

Sam Moses filed this NewCarTestDrive.com report from the Columbia River Valley.