My goatee is half and half. Brown mustache and some gray on my chin.
I started graying on the chin at 27, when I had very dark, dark brown hair. The temples followed a few years later. This is not a-typical for my fair skinned Irish heritage. By my early 50s, I was all white and extreeemly thin on top. I never fretted over any of it, going bald or turning white. There are a lot worse things that can happen to you in life. Now, with my tight, clippershaved, MPB haircut, whenever the conversation in my perr group turns to balding and graying, I just quip, "I'll take every white/gray hair I can get". My wife likes the tight buzz, and we had agreed when we married that neither of us would color our hair as we aged....what's that song, "Don't go changing, I like you just the way you are"? It could be taken to mean, let nature takes its course and do the best with what you've got. I think that's what we generally espouse here re hairloss. So, I am Ok with white and bald, and thankful to be healthy. I have to say, while I never fretted over my thinning hair, for some reason, I did find it difficult to embrace actually buzzing my hair...as much as I wanted to do it. And now I am very happy with my tight #0 buzz and occassional shave...I do think it makes me look younger. This site has been very helpful in that regard.
One of the downsides to a greying beard, particularly if you have a light complexion, is that it can blend in with the skin and look somewhat invisible from a distance. Or having grey patches can actually make it look like there are bald spots in the beard. I've found that letting the beard grow a bit longer can make a huge difference and make the grey a lot more bearable.