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. In general, both TVs cater to modern entertainment needs, including streaming, gaming, and everyday viewing. If you're comparing TCL 85S455-CA and TCL 85Q9BK, both models come with modern features and are designed to deliver a solid viewing experience across different use cases. 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. Both TVs come in similar screen sizes, making them suitable for comparable viewing setups and room environments. Both TVs provide standard built-in audio performance suitable for regular usage, though external speakers can enhance the experience. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions.

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