No downsides of going grey for me. Two years ago, with the encouragement of my sister and help of the young woman who cuts my hair, I was able to go completely natural in about two months. I have a pixie cut (and have for years).
I do not worry about roots; I can wash my hair every day, twice a day if I want, without worrying about the color fading. I am not out to impress anybody and I think the natural salt and pepper coloring enables me to be comfortable with my choices of animal print eyeglass frames and artisan styled earrings. I am more myself than when I was younger.