Please don't start this s**t again, some people love them and swear by them and others think that they are b*lls**t.
Good effort pwadjo, thats was a great answer, was it really so hard to simply reccomend that he do a search on the forum... if you dont like the subject, dont comment.
I personally dont use one, but admit that every now and again think about getting one, i do have a friend that is now a Quadriplegic after a cycling accident, and think that had they been available then, would probably have saved him.
I think for those that use them have simply got used to riding with them and put them on without thinking just like they do with theyre full face, and those that dont use them, think theyll just get in the way or have the mindset that theyll never need it, or simply doubt the technology.... the truth is, you just never know how bad that next 'off' is 'gonna be....
Some just cant afford them.
Better to be safe, than sorry.