I know a dh'er who jumps fairly large dirt jumps with clipless and he seems fine. I didn't even know he had clipless before he showed me.

I am also thinking of maybe going clipless, cause it gets quite hard controlling the bike going down long rocky downhills, cause I constantly lose my footing. Its fine going down slowly then its really easy staying on but if you speed up a little too much then you start losing your footing. If you lose your footing and you start bouncing up and down and eventually fall on your seat, I'm sure there isn't much worst injury than having the family jules crushed