OK
Your real world, actual hands-on, experience.

Do you work in a lab?
OR
Do you personally do a ton of drill mounts?

What are your guidelines on drill mounts in those materials?

PLEASE
PLEASE
PLEASE
For f-sake if you don't know or you just want to repeat something you saw or heard on the internets keep it to yourself.
If you don't work with those materials in drill mounts then you don't have an answer.