Samsung Q80/Q80A QLED vs Sony X90J

The Sony X90J and the Samsung Q80/Q80A QLED are quite different because they don't use the same panel type. The Sony uses a VA panel with a much higher contrast ratio, making it better suited for dark rooms, and the Samsung uses an IPS-like panel with much wider viewing angles. They both have a full-array local dimming feature, but the Sony's performs better because it doesn't cause uniformity issues like the Samsung's. On the flip side, the Samsung has a wider color gamut and gets brighter overall. It also has lower input lag and it supports FreeSync, which the Sony doesn't.