Many goggles have little side-vents (like the pair in this picture) on the side of each eye, supposedly for air circulation.
In your experience, are these vents helpful in keeping your face comfortable, or do they simply defeat the purpose of having goggles because they'll let dust and schmutz in?
Advise me, wise ones!
(Am I the only one who can't type "goggle" because I'm typing "google" instead? Creature of habit, I am.)