I would like to claim that that 0.25 seconds is wrong and it is a lot lower.
past that difference between 1ms and 1ms GTG are not really worth while., even if the other screen has double that on black to black (that being 2ms) it wouldn't really hurt things.
you see, 2ms is same as 500Hz
Yes, eye can see difference between 24 and 30 and 60 and (and more) But for now, lets assume that difference between 500Hz (which display can't do anyway) and 1000Hz (1ms) is small enough that you wont really see it.
My main concern with the display manufacturers rates is that they are usually taken at "boost" or "superfast" mode, which also includes big problems in ghosting and image blur. I would say that said monitors are closer to 5 or 6ms in...