Yea - "Mint" is a very loose term along with "shopped" = Hard to define.
Rating pins is a personal thing. Depends on WHY you are rating the pins. You have to take out the "emotional" aspect of the rating - Is it a game you have been after for 15 years ? "Rating" the pinball becomes a blurry line - "I just HAVE to own it" !
Like I said - everyone has a differnet rating system - Here's mine;
Backglass
No flaking, cracking or fade = 9/10
Minimal damage by one of the above = 8/10
More than minimal from one of the above, or two of the above = 7/10
Considerable damage from one of the above - 6/10
Considerable damage from two or more of the above - 5/10
Playfield
No wear and clearcoat or mylar intact = 9/10
Mylar lift, insert wear, decal wear - but repairable = 8/10
Any areas worn to wood = 7/10
Considerable wear, mylar lifting paint, clearcoat dull = 6/10
Multiple wear areas to wood = 5/10
Everything else on a pin is fixeable - so I don't really rate them - other than the body - but repaint or re decal can fix that !