Hello,
After some research i didn't found any documentation about oracle administrator needs to make "su -" .
In my opinion "su -" should never be used, instead should be used "sudo" or sudo and specific scripts/commands.
Few days ago i had a discussion with a coworker and he said the an installation/configuration of an oracle product (database, db cluster, etc.) with "su" is not same as an installation/configuration using "sudo".
I want to open a Pro/Con discussion to make an idea of Oracle Database Administrator best practices guide or better to get an official oracle "how to" or "best practices" .
Regards,