The four-cylinder engine works well around town and cruising at high speeds, but it doesn't have a lot of power at altitude on winding roads. The manual gearbox works well. The clutch pedal is easy to operate and it's easy to shift smoothly and.

The V6 engine in the Kia Optima is so smooth and quiet that one of our colleagues got into one with the engine idling and promptly tried to start it. It's that polished, and the impression doesn't fade once the Optima is underway. The engine quietly goes about its business, at least until given full throttle. Then it's still smooth but it can be heard sonorously churning out power. The V6 and automatic are a responsive team. The V6 surrenders 2-3 miles per gallon, but seems worth it for the smoothness and improved response.

The Optima's automatic transmission is a good match for the V6 engine. It shifts imperceptibly in normal driving. Slam the gas pedal down and it quickly downshifts. The transmission also has a manual-shift feature: Sliding the console-mounted shift lever over to the right allows the driver to shift up and down with a flick of the lever. It's sometimes helpful or enjoyable to slap the lever over and downshift manually to pass, but it's not necessary. This system is built by Kia, but was designed by Porsche and is similar to the Tiptronic.

Kia tuned the Optima's suspension for comfort, not handling. That doesn't mean a floaty, imprecise ride. It's smooth and stable at high speeds. It doesn't feel as connected to wet roads as a Honda Accord or Mazda6, though. While hustling down some back roads, the Optima displayed remarkable poise over bumps and lumps in mid-corner, its line not diverted by bumps in the road. The Optima operates best in its comfort zone. Push it really hard and you begin to see more chassis flex than that of the leading brands. The nose dives under hard braking and the rear squats under hard acceleration. There's considerable understeer (the tendency of the front tires to lose grip before the rear tires, causing the car to describe a wider arc in a corner). Also, the steering is relatively slow, so you have to turn the wheel more than you do in an Accord.

Kia engineers have managed to filter out most road and tire noise, but there's a ruffle of wind noise from the top of the windshield. Overall, it isn't quite as quiet as the Hyundai Sonata. At highway speeds, conversations between front and back seat were easy at normal speaking volume.