Robustness of ET-systems for crack detection

We have many years of experience of MT as a method for detecting cracks on crank- and camshafts with in-line equipment.
I am cosidering a, more or less automated ET-equpment as an alternative to this..
I am looking for any testimonials of ET for crack detection in high volume production of these kind of products.

What are the main Pros and Cons?

- Detectablilty?

- Reliability?

-  Education level of operators?

- Speed/cycle time?

- Additional MT beside ET?

Happy for any experiences out there!

Br/Jari Olavison