I used the mini multi-stringed light with one string light that would blink off and on slightly. Made the tree look like it was "sparkly". Never gave anyone a visual problem. White lights were just too plain imo. But this year the multi-colored mini lights weren't working so I purchased the C-5 Led lights to go on the tree. Love them! They look gorgeous on my tree with all the other decor that I use. Haven't heard about any visual problem or hurting anyone's eyes to look at them. Always get compliments
But I have heard that they're working on improving the Led lights to give a "warmer glow". But the ones I have already do that!