The grey isnt bothering me so much, id sooner be grey than bald anyhow... You're right though, they just seem to appear out of nowhere..
I have quite a baby face so im told, I still get ID'd regularly so if the worst were to happen to my locks my youthful appearance would certainly be the end of that.
Only a year or so back I was refused a lottery ticket due to no proof of age, apparently I looked 15???? She was clearly a bit stupid because as young as id like to think I look I dont look like im at school..