From past experience, helmets work well, very well. In fact it protected me from having a stick poking out of my head, as i found out. I hate fast crashes or stacks, there scary and you can sort of see them coming. I've only had 3 stacks that i can rembmber.
1. was walking my bike and fell over it, god everybody was laughing.
2. Took the wrong way down an off-road path, lots of really high grass and sticks and i was going so slow my front wheel got stuck in a little hole and i went over the handle bars (luckly no one was around
)
3. High speeds down a hilly, unpaved road in the mountains, and i was too fast, i started to drift off the side of the road, where it curved down and i couldn't turn becasue of my speed, went straight off the road into plently of bushes.
It funny how most or all stacks were you dont hurt yourself are very funny.