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. TCL 70S434 and Hisense 70H78G offer different motion rates (120 Hz vs 60 Hz), which can impact smoothness during fast-moving scenes like sports and gaming. TCL 70S434 and Hisense 70H78G 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. TCL 70S434 and Hisense 70H78G differ in resolution (UDH vs 4K 3840 x 2160), 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. Both TVs offer adequate brightness levels suitable for most indoor lighting conditions.

Verdict: Choosing between TCL 70S434 and Hisense 70H78G depends on your usage, whether you prioritize display quality, smoother motion, or smart features.