I spent every working hour for ten years in armor.
There’s a particular funk that is hard to describe.

External rigs are better but your undershirt will never be the same.
Sports wash, detergent, doesn’t matter, at a certain point nothing short of bleach is killing the funk.
I burned all my undershirts when I got out (blue and black don’t bleach well).

I put on CCW and advanced classes.
I have yet to wear armor for any of them. Higher class of students? Probably not. Laziness on my part.
I no longer have to race to the sounds of gunfire, so unless someone is coming after me out of the blue, its unlikely I will need armor again.