Going to be hard to judge - most mid-90's B/W games saw arcade life, so much higher risk of abuse and potential number of games making them more "used". More and more Sterns are sold new to home use, so it'll be easier probably to find nice examples down the track, and we may not see much in the way of Sterns from arcade type use. Interesting question.

Ive had my T3 about 8 years NIB
lifted the PF once to do work on it,  resolder a coil

IM worked one it one  pop bumper issue

CSI   worked on it twice  skull ramp and a opto problem

Spidey  never worked on it

TSPP (gone) worked on a flipper problem once

compared to myWms bally games-   the sterns are almost problem free
(keep in mind all but the csi  were NIB)

so as Nick said they wern't beaten to death in a arcade