THE LONELIEST NUMBER No Longer; With this new BMW, you can have as many as three friends with you at all times.(News)

Byline: MARK VAUGHN

The new BMW 1 Series has all the sound engineering of its bigger Bimmer brothers-perfect balance, powerful powertrain and great fun to drive-but at a somewhat more reasonable price. That goes for the coupe and, for the most part, includes the convertible, the subject of today's drive.

The 1 Series convertible looks better than the coupe, because putting the top down minimizes the abbreviated look of the coupe's rear end. And without the roof, the convertible adds only minimal, though noticeable, twists and shimmies. That also means there is a little less of the solid cornering of the stiffer coupe, but that's only detectable by BMW standards-the convertible is still solidly connected to the ground and ready for fast fun.

We recently had the good fortune to spend a day driving both the 1 Series coupe and the convertible and came away-for the most part-smitten. They're fun, the more so the harder you push them. The convertible is the news here, but we found both cars well engineered from top to bottom.

On the road, nothing is lacking when you push the 1 Series to its limit. When space and safety permitted, out in the middle of nowhere, where we could see well ahead of us and there were no side roads popping out of trees, we opened it up. It stayed flat and secure, even over road undulations and on- and off-camber whoop-de-dos that would upset a lesser mount.

We noted in particular some quick transitional bends on Route 84 north of Santa Cruz, California, where the road went from on-camber to off-camber and then back again, lightening the chassis considerably for a second. It was a road that would have flipped less stable cars into the weeds, but our 135 tracked true straight through. The standard sport suspension on all 135s (optional on 128s) surely helped. All models of the 1 Series get electronic limited-slip differential, DSC, dynamic traction control, front struts and a five-link rear suspension. You can't complain about any of that.

The 135i, which we drove on our day in the hills around Monterey, is powered by BMW's superb 3.0-liter, 300-hp, 300-lb-ft twin-turbo, the same mighty inline-six-cylinder powerplant that drives many BMW 3s and 5s. The 128i gets the same 3.0-liter straight-six minus the turbos. Its engine makes 230 hp and 200 lb-ft. Both drivetrains come standard with six-speed manuals; six-speed automatics are optional.