On a recent journey I had a Fenner tyre coupling fail. Fortunately, thanks to RCR, I was able to continue within a couple of days. The failure was caused by the clamping screws that tighten the taper lock bush onto the shaft becoming loose and the bush banging against the keyway everytime I changed gear until it broke. Two engineers who came to look at it said that they had come across the same problem with this unit on engines from a small Mitsubishi to an RN, and wouldn't touch them with a barge pole. On the other hand, these taperlock shaft couplings appear to be an industry standard with several million in service on all manner of equipment. Who is right? Have any members any experience with these? Would I be better off swapping it for a Centaflex or R&D coupling although on paper, they are less tolerant of misalignment?