Gray Hair

[Approach]

I think there have been similar posts to this, but I just want to understand gray hair a little better.   

1) I started getting gray hair 5 years ago.  Are salt-pepper HT grafts easier to detect, or harder to detect than a man with a solid brown head of hair? 

2) Can you give any other suggestions / advice things I might want to discuss with the doctor about my gray hair?

Thanks