The Samsung S90D OLED 55 outperforms the LG C4 OLED 55 in brightness (1400 nits vs 800 nits per RTINGS) and motion clarity with its 144Hz panel, making it the stronger pick for bright rooms and gaming. The LG C4 counters with native Dolby Vision support and a more polished webOS interface. Both are 2024 models now superseded by 2025 lines like the LG C5 and Samsung S95F.