I don't attach a mirror to them but I do wear clear safety glasses when it's not bright enough for shades. They were about $6 and help with wind, rain & flying objects. They have deflected a truck-tire-flung stone that would have damaged my eye!
Also handy on trails for mud, water, sticks, stones, bugs, etc.
In certain low-light conditions I switch to yellow-tinted safety glasses instead of clear. Also $6.
Every local hardware/home improvement/building store has 'em.
Cheers!