I never ski without one and have been in one for about 22 years now.
Current is a Uvex Ultra Wing
When my boys were still racing we were over at White Pass for the annual Bantam Cup. (A Mighty Mite 12 and under race) An adult forerunner dresse up in a Rooster suit for his run!
It was gorgeous out but snow was hard as a rock. Sincethe weather was so nice , I decided, well I am not going to wear my helmet this morning.
Went out and took a run and immediately skied back tot eh lodge and put my helmet on. I felt so uncomfortable and vulnerable, I had to get my helmet.
I am pretty sur that is the only time (1 run) I have skied without it in 22 years!