For an soft realtime application like game that’s the difference between 10fps and 30fps. Or 30 and 90. Basically total failure or success.
I was referring to response time in a GUI app -- 9ms is undetectable.
Again, if you have a reason the speed matters, then it matters. The specific numbers here are not relevant to my argument, which boils down to: being "slow", in and of itself, is meaningless.
I'm not going to care about the difference just because "omg one number is 3x another number!?!"