TCL 65S434 and Hisense 65H78G differ in resolution (UHD vs 4K 3840 x 2160), which can affect overall clarity and sharpness of the display. 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 65S434 and Hisense 65H78G are two competitive smart TVs offering a mix of display performance, smart features, and overall value for different types of users. Both TVs come with smart platforms that support popular streaming apps and voice control features. TCL 65S434 and Hisense 65H78G 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. From a practical standpoint, both options provide a reliable viewing experience for most users.

Verdict: Both models offer good value, and the better option depends on your specific requirements and viewing preferences.