I'm too cool to wear a helmet. Actuallly I should probably get one but I like my condom hats. Oh well, too many horror stories relating to head injuries,
over cus under is just plain stupid i did it last year and everytime i would fall my goggles would go down to my neck and i wouldhave to take off my helmet everytime and its just really annoiying ecspecialy if you have tune ups it makes the sound quiter since it has to go through your goggle strap
thats what happened with mine, i tryed it under but the clip on the back of the goggel strap just pushes into my head and it really hurts after afew runs