My question is more theretical than practical..

Does usage of different OSes give you advantages in QW in such areas as input latency or perfomance, or better preemptive multitasking..?
Does FreeBSD, or something like vxworks, QNX provide better user input response times..?
And by the way does interrupt-based PS/2 port give you better response for keyboard input than USB keyboards (125-1000hz).?
(for mouses answer is clear to me - i prefer 250-1000hz USB over 200 PS/2)

Thanks.

I dont think so. What you feel comfortable...

Back in the days svgalib-based mouse on linux was much better compared to WinXP's crappy mouse handling. But I don't think there is any difference nowdays.
It all boils down where do you have more fps (which OS).

Siounds like a question for raket. Hahahaha.

NO idea..

Usb is faster(1000hz ofc). If you add setup and install time, windows is better. : P~~
Linux might have slightly lower latency on devices like mouse and keyboard, windows might have faster gfx. The difference is in single digit milliseconds.. : ]

..and it's the last milliseconds you can get..