that's a sensitive subject, the history of the vet from their perspective is an important part of history but its one that belongs to the vet alone. if they already have it all written up and are will to share that then great and if you know the person very well and they are comfortable enough about it to talk than maybe ask, but be very very carful about how you ask. the fact is that some of these vets are getting rid of their gear because it reminds them of the history that you would be bringing up. they may have had an uneventful time or they may seen a version of hell you cant even begin to imagine.
let me put it like this, lets say you just had a real nasty divorce, you are feeling hurt, you cant stop thinking about it, you cant help but think if only this or if only that. you lost kids or only get to see them once in a while, she took your car and maybe your house. you manage to coupe but after some time you decide to move one because what else can you do and one of the first things you do is go to get rid of the stuff that reminds you of your past life. you still need money (maybe now more then ever) so you go to sell some stuff. the guy buying it says yep I will buy it but first I want you to go home and think real hard about everything you experienced in your life with your wife and kids and put it down on paper for me. I am really interested in the juicy parts, like just how it felt when so walked out and what you were thinking when your kids where crying because dad could not be there anymore.
now imagine how that would make you feel before you ask a vet for a detailed history of their service down range. some of these guys and women are dealing with some real heavy stuff and if you go trying to drag it up you may hurt them, even if you don't mean to. that's why I for one never ask for a lot of details unless they bring it up. to be honest I have walked away from some talks feeling very emotional my self over just hearing what some of them had to deal with.