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. TCL 85S455-CA and TCL 85Q9BK offer different motion rates (60 Hz vs 144 Hz), which can impact smoothness during fast-moving scenes like sports and gaming. Overall, both models are capable choices in their segment, offering a balance between performance, features, and usability. TCL 85S455-CA and TCL 85Q9BK are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities. Both TVs come in similar screen sizes, making them suitable for comparable viewing setups and room environments. TCL 85S455-CA and TCL 85Q9BK differ in resolution (UHD vs 4K 3840 x 2160), which can affect overall clarity and sharpness of the display. Both TVs provide standard built-in audio performance suitable for regular usage, though external speakers can enhance the experience.

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