After seeing members and friends being seriously injured and stories of fatalities I hope to clarify which Flex Fans are the culprits of infamy and which are a good product. Any metal flex fan has the potential for fatigue, cracking and rivet separation. Any fiberglass flex fan which has multiple pieces riveted together is also a ticking time bomb. These type (below) I have never seen fail from anything other than impact.... Provided they stay below their designed RPM limits.