There is a difference in screen size (39 Inch (99 cm) vs 40 Inch (102 cm)), and a larger screen generally provides a more immersive viewing experience. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. Both TVs come with smart platforms that support popular streaming apps and voice control features. Both TVs provide standard built-in audio performance suitable for regular usage, though external speakers can enhance the experience. Overall, both models are capable choices in their segment, offering a balance between performance, features, and usability. VU VU-39E7575 and Sansui SMC40HB21C differ in resolution (1920 x 1080 vs 1366 x 768), which can affect overall clarity and sharpness of the display. Both TVs provide decent motion handling, making them suitable for everyday viewing including sports and action content. VU VU-39E7575 and Sansui SMC40HB21C are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities.

Verdict: Both TVs are strong contenders, and your final choice should depend on your preference for screen size, motion performance, and smart features.