When using Set Members in struct, you are able to hide all pins you do not want to change. This is great, however if you change anything about a variable in the struct itself (its type or its name), the pin associated to this variable will be automatically unhidden in EVERY Set Members in struct for that struct type.
This has the very annoying effect of setting that variable to something you don’t want (0 or null) and its extremely hard to track down if you use Set Members in multiple places, because it doesn’t give an error (since its not one).
It makes the Set Members node too unreliable to use in a large project where elements of a struct are changed in multiple places.
To illustrate:
The original Set Members node
Set Members node with all other pins hidden.
The Set Members node after I changed the name of the Actor Class variable. The Actor Class will now be set to Null if I don’t manually re-hide the pin.