What is the commonly accepted size for the SEP 12 AV definitions folder?

I have come across one article that says this:

Threshold (April, 2014)
11.x and 12.0.x: Directory > 6.5 GB
12.1.x: Directory > 7.5 GB

I know that those numbers do not represent the maximum. Not by a long shot. I am thinking that they represent the number after which you should likely be concerned that av def cleanup has failed and you should consider going through the manual av removal which is a pain, or simply cleanwipe/reboot/reinstall SEP/reboot.

Whats your input of what you feel should be considered a normal size for AV definition folders?