2009 BMW Z4

The BMW Z4 convertible is fast, testers say. It squeezes the same top-level engine as the four-seat BMW 3 Series convertible (*Est. $44,550 to $50,700) and BMW 1 Series convertible (*Est. $34,000 to $40,150) into a smaller, lighter car. Car and Driver testers sprint from zero to 60 in just 4.8 seconds -- faster than BMW advertises -- in a top-level BMW Z4 sDrive 35i (*Est. $51,650) equipped with the 300-horsepower, 3.0-liter twin-turbo inline-six engine. Even the base engine isn't slow in tests: the BMW Z4 sDrive 30i's (*Est. $45,750) naturally aspirated, 255-horsepower I-6 dashes to 60 in 5.6 seconds.

The BMW Z4 convertible offers three transmissions. Experts especially like the smooth-shifting six-speed manual that comes standard. Expect 19 mpg city, 28 mpg highway and 22 mpg combined with the base engine, 18 mpg city, 25 mpg highway and 20 mpg combined with the turbo.

On the base BMW Z4 sDrive 30i, you can opt for a six-speed automatic with shift paddles, with just a one mpg loss in highway fuel economy (19 mpg city, 29 mpg highway and 22 mpg combined). The step-up sDrive 35i offers an optional seven-speed, dual-clutch, automated manual transmission instead. Again, fuel economy barely suffers (17 mpg city, 24 mpg highway and 20 mpg combined), but experts say this transmission isn't as brilliantly executed as the Porsche Boxster's rendition of the dual-clutch automated manual. In addition to the powertrain differences, the costlier Z4 sDrive 35i includes leather seats and automatic climate control as standard equipment; they're optional on the sDrive 30i. (SDrive is BMW's nomenclature for the Z4's two-wheel-drive powertrain. Other BMW models that offer all-wheel drive get the xDrive moniker instead.)

You sit pretty far back in the rear-wheel-drive BMW Z4, looking out over a long expanse of hood -- which testers say can make it hard to know where the front of the car is. Jalopnik.com's Wes Siler says it might feel like the Z4 suffers from body roll, until you get used to the feeling of sitting practically on top of the rear axle. But other experts say no, the Z4 really does roll too much in corners -- at least compared with Porsches and other BMWs. Several reviewers say the steering feels oddly light for a BMW, too.

We found no government or independent crash tests for the 2009 BMW Z4 as of this update. Previous Z4 models have enjoyed good reliability, and the Z4 carries four-year, 50,000-mile basic and powertrain warranties.

Car and Driver conducts the best comparison test of the 2009 BMW Z4, pitting it against three similarly priced performance convertibles. Edmunds.com provides a wealth of pricing information and specs in addition to thorough testing, but its review -- like those at TheTruthAboutCars.com, Autoblog.com, Jalopnik.com and The New York Times -- draws only brief comparisons with other cars. ConsumerGuide.com tests the Z4 and rates it in several areas, with brief explanations. ConsumerReports.org had not yet fully tested the Z4 when we checked, but reliability data here can be helpful. We found fuel-economy estimates at the U.S. Environmental Protection Agency's website, FuelEconomy.gov.