What's not to like about small BMWs with big engines? Not much. But the coupe and convertible are like fraternal twins, female and male. One, the convertible, is attractive with alluring ways; the other is tough and blunt. Both have a full measure of engineering and drive with the integrity of purebred, rear-wheel-drive BMWs.

The 128i coupe has a starting price of $29,425, including the $825 freight charge from Leipzig, Germany. This model features a 230-horsepower, 3.0-liter inline six-cylinder engine. With 200 foot-pounds of torque, it scoots to 60 mph in 6.1 seconds with the six-speed manual or 6.7 with the optional six-speed automatic.

The 135i coupe starts at $35,725 and can run to $47,000 or more. It has a twin-turbocharged, 300-hp version of the 3.0-liter. There is no turbo lag and the launch force is stunning, reaching 60 mph in 5.1 seconds, according to company statistics.

The top speed is electronically limited to 130 mph, or 149 with the sport package.

I recently drove the 135i convertible and 135i coupe. The convertible, $44,775 as tested, is smooth and refined in steering, braking and handling. The coupe was a handful, with much stiffer steering and a more aggressive attitude. And its price was a staggering $46,780 as tested.

Even with its masterpiece of an engine, the coupe will live in the shadow of its 3-series brother, which may be the most handsome coupe on sale today. The 1 series draws some styling influence from the vintage 2002 models, but the shape seems to be the offspring of a committee that could not decide whether it wanted a two-door or a four-door.

There are traditional BMW design cues in the face and tail and Hofmeister kinks at the rear roof pillars, but the rest is generic. Spoilers and aerodynamic panels applied to the 135i still don't give it identity. If the styling is about multiuse function, two more doors would help back-seat access. There's a five-door hatchback in Europe, which has better looks and more access, but there are no plans to export it here.

Rear access isn't such an issue for the convertible. And it's cute.

It's not the power that makes this car so enjoyable, it's the packaging. It's small, but not cramped, and more like the BMW 3 series of a couple of generations ago. It is also $10,000 less than the new 3 series with retractable hardtop.

The 135i convertible starts at $39,925. In comparison, the 128i is $6,000 less but gets just one more mile per gallon. Where's the value in that?

The test 135i soft-top wasn't loaded with options, but those it had were desirable. The Coral Red leather upholstery ($1,450) is beautiful, and it doesn't burn bare flesh on hot days. And $1,000 for the Sport Package buys the thick, three-spoke "M" steering wheel and includes 18-inch wheels and sport seats. The Comfort Access System ($500) is the "intelligent" locking and starting system. With the key pod in pocket or purse, the doors lock or unlock when grasped, and the ignition is push-button start. BMW finally got this system right and it saves time and effort.

Same with the top. Press and hold one button, and the lined and insulated cloth top folds and retracts in 22 seconds. Even if the traffic light turns green before the process is finished, the top action continues up or down at speeds to 25 mph. Airflow is ideal at all legal and sane speeds, at least for front occupants. The back window is glass and heated. The top goes back so easily that I had to force myself one summer's morning to drive with the top up to check visibility. Sightlines over the shoulder are forgivable. And when the top is up, the cabin is tight and quiet enough for normal tones of conversation.

BMW's six-speed manual is what the competition tries to emulate. It now integrates what BMW calls a start-off assistant, which brakes the car while engaging the clutch on hills. The fear of stalling is gone.

For those who positively won't use a manual, the six-speed Steptronic automatic ($1,275) is lively and well-suited for performance driving.

The 135i's 300-hp is always enjoyable and has that fine, well-muscled BMW tone. Fuel mileage ratings are 17 mpg city and 26 highway, manual or automatic. The 128i has mileage of 18/28 manual, 18/27 automatic. Premium fuel is recommended for both engines.

Other assets include:

Plenty of trunk space when the top is down.

Plenty of interior storage and a locking glove box of adequate size.

Four years or 50,000 miles of free scheduled maintenance.

Flaws are few. The faux burl walnut trim seems very middle-aged in this youthful, sporty car. Bamboo or other textured effects would be preferable. And these Germans seem to think that seat heaters require a ski-bag pass-through for the trunk, a $600 package. Seat heaters should be standard for all convertibles.

The 1-series coupe is an enthusiast's car, and its sophistication will likely go unappreciated in the United States, where coupe success is about styling and the horsepower-to-price ratio. Where does this BMW fit in with the new Mustangs, Challengers, Nissan 350Zs and Camaros? Even the Honda Accord V-6 has looks and costs thousands less than the BMW.

Despite its engineering credentials, the coupe will have to duke it out for sales, but from these family genes came a terrific new convertible.

SPECS BOX

2008 BMW 135i convertible

Body style: compact, four-seat, rear-wheel drive, soft-top convertible

Engine: aluminum-magnesium, 300-horsepower, twin-turbocharged, 3.0-liter, inline

six-cylinder

Transmission: six-speed manual

EPA fuel economy estimates: 17 mpg city, 26 highway; 91 octane recommended

DIMENSIONS

Trunk space: 9.1 to 10.7 cubic feet, top down/up

Front head/leg/shoulder room: 38.6/41.2/54 inches

Length/wheelbase: 172.2/104.7 inches

Curb weight: 3,660 pounds

SAFETY FEATURES

Safety features include: dynamic stability control, including brake fade

compensation, start-off assistant, brake drying and brake stand-by; four-wheel, vented anti-lock disc brakes with dynamic brake control

PRICING

Base: $39,925, including $825 freight charge; price as tested: $44,775

Mark Maynard is driving in cyberspace at mark.maynard@uniontrib.com.

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