OLED displays also have very low latency as long as there is no scaler in the way. The Oculus Rift CV1 uses them and has a motion-to-photons latency of 9 ms[0], which includes not just the display but the entire stack.
Yeah, scalers and OSDs are going to be the hardest things to give up.
I will admit ... it's painful using my ZR30w with no scaler. I can't connect my PSP's component out to it, I can't hook up my Wii U, I can't connect my XRGB Mini, my Raspberry Pi, etc ... because none of them output at 2560x1600.
Even worse, the DisplayPort connector stopped working on it (hooray, $1300 monitor quality!!), so all I have is one DVI port left, which can't even output at the 30-bit color depth which was a big part of why I wanted this monitor :(
The ironic thing about OSDs causing input lag is that the very systems we emulate prove that video overlays are trivial to implement without buffering.
According to popular consensus answer was SED which eventually lost to LCD.
https://en.wikipedia.org/wiki/Surface-conduction_electron-em...