Both TVs offer adequate brightness levels suitable for most indoor lighting conditions. 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. Toshiba 43C350KU and OnePlus 40 Y1 are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities. Both TVs come with smart platforms that support popular streaming apps and voice control features. Audio output differs between the two (2 X 7 W vs 20 W), which can influence overall sound clarity and loudness. 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. Toshiba 43C350KU and OnePlus 40 Y1 differ in resolution (4K 3840 x 2160 vs 1920 x 1080), which can affect overall clarity and sharpness of the display.

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