8-bit panels I think. My favorite feature of the original 90 series (not found in the 90 v2 or PA series) is the A-TW polarizer because it reduces the IPS off-angle glow to a great degree. Also the ColorComp function, which makes the screen's luminance super uniform is awesome. If the PA series had the A-TW polarizer I would buy one right away. Aside from response time I think the 20WMGX2 has been easily surpassed, for example the 90-series or PA-series also by NEC.