I haven't used 40Hz so I can't speak for it but at 30Hz even my typing is slower, let alone mouse movement, which feels like it's pulling on a short string. 60

I haven't used 40Hz so I can't speak for it but at 30Hz even my typing is slower, let alone mouse movement, which feels like it's pulling on a short string. 60Hz is a good sweet spot, but as people say 120Hz is noticeably better. At least at 60Hz I can type at full speed, scroll at full speed, and my mouse accuracy when clicking on buttons is good enough.