The average human reaction speed is about 200ms. I just can't see how a 5ms radio can have that much appreciable difference over a 10ms radio. I know a lot of people say they can tell the difference, but I think a lot of it is a placebo-type effect. You get a fancy new radio that is marketed as being faster, and your brain (consciously or subconsciously) wants to believe that it's helping. That said, I don't doubt that getting a different radio can help to make someone faster, I just think there are many more factors to it besides the latency of the signal.