I use a tinted visor, as dark as I can find. I've had helmets with the drop-down sunshades, but I just don't like them as much due to the optical quality (yet another layer of plastic that I have to look through -- I wear prescription glasses) and how easily they get dusty and scratched up. Sometimes I will even wear my prescription sunglasses with the tinted visor if it's bright and sunny. I always bring a clear shield with me, unless I know that I'm just going to be out for a little while with no risk of heavy clouds or night. As an added benefit, a good tinted visor really reduces the radiant heat on my face, which can be a big deal down here.