2009 BMW Z4 Convertible

Performance and Design: Taken from the Automotive Performance, Execution and Layout (APEAL) study, this measure is based on owner satisfaction with vehicle Performance, Style, Features and Instrument Panel, and Comfort.

Initial Quality: Taken from the Initial Quality Study (IQS), which looks at owner-reported problems in the first 90 days of new-vehicle ownership, this score is based on problems that have caused a complete breakdown or malfunction, or where controls or features may work as designed, but are difficult to use or understand.

Predicted Reliability: Derived from historical trending for a vehicle and/or manufacturer in our Initial Quality and Vehicle Dependability Studies, Predicted Reliability is a forecast of how reliable a newer vehicle might be over time.

Overall Dependability: Taken from the Vehicle Dependability Study (VDS), which looks at owner-reported problems in the first 3 years of new-vehicle ownership, this score is based on problems that have caused a complete breakdown or malfunction of any component, feature, or item (i.e., components that stop working or trim pieces that break or come loose).