This is my thoughts on "mint" vs well loved or character.
I would be wary purchasing a mod that is older or real old that looks too perfect. Very tempting, but what comes to mind right away is either the
device has been sitting in a box and not used, big plus... OR its been over maintained and pampered to the point that its been polished with abrasives on a reg basis and it could now be a lot "thinner" in metal thickness that it might have been compromised to where its now much thinner than it was.
Ok, Im kinda OCD, and think of the worst.... But I have seen some in that condition. Some mods are made of very thick material and heavy, some are light, which means they were thin walled to start with, use an abrasive constantly and eventually its weakened.
I got a PAPs once and knowing how they feel could tell that this tube was either a clone ( doubtful because of who I got it from ) or its been polished a lot or by someone that had too heavy a hand, or it got dropped and got a deep gouge and to smooth it out , it had to be buffed/ sanded enough to make it look like new but weaken that point.
I dont mind character and surface scuffs, etc. I rather have a well maintained but sound tube than a visually mint but weak piece of metal.
I use Simichrome when I get a new item, I only hand buff it, because Im afraid of using a power tool. After that I might do it a couple more times in case it has a lot of scuffs, but thats it. I never use an abrasive again.
If you want your device to be "mint/museum/ to re-sell for as much or more" then you are very strong willed and logical or you get 2 one to love and use and one for as an investment.
Me? I always take my expensive action figures out of the package and fondle them....