ORIGINAL: Tarasdad
Wood props are more likely to break when they hit a solid object (such as, say, a portion of your anatomy) than plastic or nylon props. Either is bad news if you get hit.
I can attest that "likely to break" tends to be an exception to the rule... I have the scars to prove it.
However wooden props ( particulary on large gassers ) tend to be more crankshaft friendly during nose overs.