Is the crank sensor and reluctor ring ok?

I have had very weird things with these, you may be aware the bottom pulleys come loose, I've had two now that had come loose before their first cambelt change, and where there was supposed to be a groove in the reluctor for the crank keyway it had worn a slot, causing very odd running conditions and misfires etc as the reluctor jingled around.

Not quick and easy to check , but something I have spent hours chasing.

Liam.