Not quite all of them Sas. Probably 4 out of 6 (1 crash, 1 ditch).
Bristow actually ordered 5x BV234 if you remember then cancelled. Although there were many reasons for the cancellation, there was a genuine concern regarding transmission failure and its likely catastrophic effects with the then Engineering Director and Operations Director.
A letter or memo expressing the concern was written, can't remember who the recipients were, we are talking 1979-80 era, just before the announcement of the AS332L order. I once had a copy but its long since gone.