These glasses look cool, but literally do not stay on my head without a helmet or hat pushing down on them. The arms of the glasses are not straight so you cannot capture them under your helmet. They curve weirdly and spring up on your face if you don't have anything to push down on them.
The lenses are nice and big, but come up high on my forehead, sealing in all of the sweat and steam while I ride. By pushing them down my nose a bit they seem to breathe better. The final let down for these glasses was the little rubber insert on the ends of the arms of the glasses that catch my hair and rip it out every time I put them on or take them off. The inserts have gaps that don't allow for a nice glide over hair strands. I'll probably have to fill the gaps with some sort of glue so it stops pulling my hair out. Given all that, once they're on and held down by my helmet they work great, blocks the sunlight and look super cool. If you have a helmet that sits low on your forehead, these will not work.