Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. Both TVs provide decent motion handling, making them suitable for everyday viewing including sports and action content. TCL 43S455-CA and OnePlus 40 Y1 are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities. TCL 43S455-CA and OnePlus 40 Y1 differ in resolution (UHD vs 1920 x 1080), which can affect overall clarity and sharpness of the display. There is a difference in screen size (43 Inch (109.22 cm) vs 40 Inch (102 cm)), and a larger screen generally provides a more immersive viewing experience. Audio output differs between the two (10 W + 10 W vs 20 W), which can influence overall sound clarity and loudness. Both TVs come with smart platforms that support popular streaming apps and voice control features. Overall, both models are capable choices in their segment, offering a balance between performance, features, and usability.

Verdict: Both models offer good value, and the better option depends on your specific requirements and viewing preferences.