Drop the top on the convertible, and you may not even notice what the road surface is like.

These cars corner like go karts. It takes some very hard driving to exceed their cornering limits. The harder and deeper you go into corners, the more the Mini says more. It goes where it's pointed without protest. Even when rain was sheeting down and the pavement shimmered in rivulets, the Mini felt bonded to the surface.

As expected from a car associated with BMW, the Mini Cooper's steering is precise and immediate, though not as light as you might expect in a small car. With its sharp and accurate steering, it's easy to place the car exactly where you want it. The suspension (McPherson struts in front and multi-link rear) is designed to keep the car snug to the road. This means passengers feel broken surfaces, expansion joints and weathered pavement. The Mini's ride is not velvety, but it is secure. Somehow even on the roughest road, one that sets passengers popping like corn in a hot skillet, the Mini holds its direction like a gyroscope. Drivers like that. And make no mistake: The Mini is a driver's car.

The brakes are equally impressive Brake hard at speed and the Mini feels sucked to the earth and stops quickly. The four-wheel disc brakes (vented in front) come with four-channel ABS, Electronic Brake-force Distribution (EBD), and Corner Brake Control (CBC). EBD distributes front-to-rear brake forces for improved stability and shorter stopping distances. CBC evens braking forces side to side, important when braking in the middle of a corner (usually a driving faux pas). Optional Dynamic Stability Control (DSC) applies the brakes at individual wheels and reduces engine torque when it senses you're skidding or not traveling on your intended path.

The standard 115-horsepower 1.6-liter four-cylinder overhead-cam engine never feels deficient. It delivers plenty of power for most of us. Its acceleration performance may not plaster you to the back of the seat, but it has plenty of power for charging around on-ramps and can rocket onto the freeway. It gets an EPA-estimated 28/37 mpg City/Highway.

Shifting feels good and smooth. The Cooper comes standard with a Getrag five-speed manual transmission (new for 2005) designed for quick acceleration.

The Mini Cooper S uses a supercharged version of the same engine that produces 168 horsepower and 155 pound-feet of torque at 4000 rpm. The S doesn't feel like a rocket off the line, but really comes into its own once it's rolling. The supercharger doesn't deliver the explosive thrust associated with turbocharged engines, but it accelerates hard, with thrilling performance when you nail it in the 30-60 mph range. The supercharged engine uses the same block, but features more cooling measures (an engine oil cooler and piston-cooling jets), lower-compression pistons (to reduce detonation), a special crank, special valves, and, of course, the roots-type blower. All this adds up to 40-percent more horsepower and torque and an EPA-estimated 24/33 mpg.

The S comes with a six-speed manual. The pull from the supercharged engine means it doesn't shift as elegantly as the standard Cooper, but it's quite tractable and easy to shift around town at low speeds. Sixth is a tall gear, good for fuel economy. The six-speed is a high-performance Getrag gearbox with double-cone synchros.

The S rides more firmly than the standard Cooper. It's fine for a driving enthusiast, but some may find it a bit stiff. You hear and feel tar strips. Some of that could be attributable to the run-flat tires. On a tight autocross circuit, the S feels quicker, more like a go kart, though the standard Cooper is still a hoot.

The available CVT, or Continuously Variable automatic Transmission, drains the fun out of the Mini Cooper. The Mini's CVT doesn't seem suited to this car the way the superb CVTs are to the Audi A6 and Nissan Murano. You may get used to it, but it's unlikely you'll ever love it. It's not as responsive as a proper manual gearbox. It bogs when coming out of corners unless you give it a lot of gas. Stand on it and it holds 5500 rpm until you lift. If you can't shift a manual gearbox, we recommend looking for another car. Or learn to shift for yourself. It's easy to do and the Mini is worth that.

For serious enthusiasts, the John Cooper Works (JCW) package is the E-ticket. With 200 horsepower, a Works Mini Cooper S cuts the 0-60 time to 6.5 seconds, but more importantly cuts the 50-75 mph time to 5.6 seconds from about 6.7 seconds for the Mini Cooper S. The Works kit includes a new cylinder head, supercharger and exhaust system. Best of all, it's fully warranted by dealers.

We drove a Works Mini for nearly 300 miles on narrow Irish roads, and were very impressed by its speed and tractability. The powerband is enormously wide, from 3500 rpm (acceleration is decent even at 3000) to redline at 7500, with peak torque increased to 177 pound-feet from the standard 155. The power was so good at any engine speed that we didn't need to shift the six-speed gearbox very much.

A drive of the latest Mini Cooper Convertible around Los Angeles showed why it's the perfect companion for outdoor enthusiasts. Not only does sunshine come standard at the press of a switch, the car's perky little 1.6-liter engine provides as much fun per fuel dollar as any car on the market. Ecologically friendly cruising has never been so cool.