Depends on the unit. This year, I received the coin of 1/221 Cav, for the stuff I did for them, out at NTC. They recommended me to the Cdr/CSM, and it was given at an informal formation. I was the talk of my unit; the only guy to get it.
Other units, it's a departure presentation for the whole tour. In 1989, I got mine from Special Security Group, as a departing XO. So both the enlisted and commissioned sides can be awarded.
And I think GWB more than qualified, don't y'all?