In this session, we discuss how the efficient unit testing of complex models and the corresponding C code needs to employ effective, as well as optimized, test cases that satisfy specific functional requirements and structural coverage. In our validation study of more than five months, we piloted Simulink Design Verifier™ for generating the controlled and optimized test cases with maximum structural coverage. The study proved that with the appropriate Objective block and Condition block settings in the Simulink model, the required objective is achievable. We can achieve the maximum structural coverage and expected range and resolution coverage of the output signals with a specific customized approach supported by Simulink Design Verifier. In this session we talk about key challenges and how Simulink Design Verifier and customized M-scripts are helping us to validate models and C code in a short amount of time.