The LG C4 OLED 42 outperforms the LG QNED80 55 on contrast and motion clarity according to RTINGS measurements, making it the stronger choice for cinematic viewing despite the smaller screen. The QNED80 55 offers more screen real estate and higher brightness for well-lit rooms but trails significantly in black uniformity. LG C4 OLED 42 is the winner for most users prioritizing image quality.