After a variety of buzz cuts, I first shaved completely bald in 1996, when I was 35. I'm 51 now, and still have a full head of hair when I want it.
That first time, I stayed sly for 6 months, and grew it back.
Since then, I go sly for at least a few months every year.
Most recently, I went sly in mid-August and shaved every day for the last 3 weeks or so. Color is finally evening out.