The Sony X800H displays a wide color gamut and has great coverage of the DCI-P3 color gamut used in most 4k UHD Blu-rays.
The EOTF follows the PQ curve well until it rolls off, but dark scenes are a bit brighter than they should be. In ‘Game’ mode, the curve is nearly the same.
If you find HDR too dim, set the Color Temperature to ‘Expert 2,’ Contrast to ‘Max,’ Gamma to ‘Max,’ Advanced Contrast Enhancer to ‘Low,’ and Picture Mode to ‘Vivid,’ and you’ll get images that are noticeably brighter, as seen here.