There is a difference in screen size (55 Inch (139 cm) vs 58 Inch (147 cm)), and a larger screen generally provides a more immersive viewing experience. Toshiba 55M550KU and TCL 58S455-CA differ in resolution (4K 3840 x 2160 vs UHD), which can affect overall clarity and sharpness of the display. Overall, both models are capable choices in their segment, offering a balance between performance, features, and usability. Toshiba 55M550KU and TCL 58S455-CA offer different motion rates (120 Hz vs 60 Hz), which can impact smoothness during fast-moving scenes like sports and gaming. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. If you're comparing Toshiba 55M550KU and TCL 58S455-CA, both models come with modern features and are designed to deliver a solid viewing experience across different use cases. Audio output differs between the two (2 X 8 W vs 10 W + 10 W), which can influence overall sound clarity and loudness. Both TVs come with smart platforms that support popular streaming apps and voice control features.

Verdict: Choosing between Toshiba 55M550KU and TCL 58S455-CA depends on your usage, whether you prioritize display quality, smoother motion, or smart features.