Overall, both models are capable choices in their segment, offering a balance between performance, features, and usability. Both models support 4K 3840 x 2160 resolution, ensuring sharp picture quality with detailed visuals for movies, shows, and gaming. Panasonic TH-58HX450 and Samsung HG55RU710NF offer different motion rates (60 Hz vs 120 Hz), which can impact smoothness during fast-moving scenes like sports and gaming. Panasonic TH-58HX450 and Samsung HG55RU710NF are well-equipped smart TVs that aim to provide a balance of picture quality, performance, and smart capabilities. Both TVs provide standard built-in audio performance suitable for regular usage, though external speakers can enhance the experience. 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.

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