Using factory ammo that a LEO also uses can land you in trouble. For the prosecuting attorney can say you “Were trying to play cop.” He suggested a good self defense loading, but not one labeled “For Law Enforcement use” or one that advertises itself as such.
Your lawyer friend is in the minority.
If a DA does try that approach you have a simple irrefutable response:”No sir, I know I’m not a police officer but I use the same ammor for the same reasons they do. Are you saying their reasons for choosing their ammo are not valid?