TCL 58S455-CA and Mi TV X55 differ in resolution (UHD vs 4K 3840 x 2160), which can affect overall clarity and sharpness of the display. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. There is a difference in screen size (58 Inch (147 cm) vs 55 Inch (139 cm)), and a larger screen generally provides a more immersive viewing experience. Both TVs come with smart platforms that support popular streaming apps and voice control features. From a practical standpoint, both options provide a reliable viewing experience for most users. Both TVs provide decent motion handling, making them suitable for everyday viewing including sports and action content. Audio output differs between the two (10 W + 10 W vs 30 W), which can influence overall sound clarity and loudness. TCL 58S455-CA and Mi TV X55 are two competitive smart TVs offering a mix of display performance, smart features, and overall value for different types of users.

Verdict: Choosing between TCL 58S455-CA and Mi TV X55 depends on your usage, whether you prioritize display quality, smoother motion, or smart features.