Our Z4 3.0si coupe was equipped with the optional Sport package, which adds a firmer suspension, a 0.6-inch lower ride height, 18-inch run-flat tires instead of standard 17s, and a Dynamic Driving Control (Sport) console button.

The 3.0si's 24-valve inline-6 is bliss, crooning its way into your heart. With 255 horsepower, it's spritely away from a stop, but it really shines at higher revs. Making that pass at 65 mph is a piece of cake and it usually doesn't even require a downshift. The 3.0si is capable of a 5.6-secoond 0 to 60 mph sprint. Hitting the Dynamic Driving Control's Sport button quickens throttle response, making the Z4 even more responsive.

The 3.2-liter engine in the M models has similar characteristics, but it makes a more gravelly sound. It doesn't knock you back in your seat off the line, but it does build power with confidence and has more performance potential than its 3.0-liter counterparts. A Z4 M is capable of a 4.9-second 0-60 run.

We haven't driven a Z4 with the base engine.

The six-speed manual gearbox is a pleasure to operate with any engine. M models have shorter, sportier gearshift throws, but all manual-equipped Z4s provide silky smooth shifts. With the Sport package, hitting the Sport button can cause the engine to wind up, then bog, especially when the engine is cold. We've experienced this minor annoyance with other manual-shift BMWs. It can be rectified by letting the car warm up or applying precise throttle pressure.

Any Z4 grips the road like a shy toddler clings to its parents on the first day of preschool. The body remains flat in corners. The only thing making you lean one way or the other is the inertia brought about by speeding up instead of slowing down for turns. Steering is quick, weighty, and precise. The car goes exactly where you put it. In a Z4, clover-leaf on-ramps are your best friends. Coupes are rock-solid, and we detected little, if any, cowl shake in the roadsters.

We had an opportunity to drive both the 3.0si coupe and M roadster on a racetrack, and we couldn't have been more pleased. In a high-speed environment, the steering feel was reassuring, the grip was tenacious, and the car was steady at high speeds. The vented disc brakes, with ABS, front-rear proportioning and electronic brake assist, were typically BMW-brilliant. We managed to heat them up, but they only smelled, they didn't fade. The Z4 has more handling capability than 99.9 percent of its owners will ever use.

Supreme handling usually comes with a ride penalty. While that's not the case for base models with their 17-inch wheels, the sport suspensions on the M and 3.0si with Sport package are not smooth cruisers. While these suspensions iron out small road imperfections, broken or uneven pavement causes a lot of up-and-down motions, and sharp bumps can jolt. We suggest taking an M or Sport package 3.0si out on the bumpiest roads you normally encounter before you buy. If you live in California, this might not be a problem, but Midwesterners might find they prefer the softer settings of a base model.