Maybe I can chime in here and at least "try" to be of some help. My uncle used just for men, but just like you, he likes to keep his hair very very short or in a crew cut style. So he was constantly having to apply this stuff over and over as his hair grows so fast. Now it did work ok, but to him it wasn't worth the expense and effort.
I think guys with greying hair is quite cute though (think George Clooney)
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