I am weary of "untested" listings and even moreso when it's from a seller that sells fully tested similar items.
Agreed. I always assume untested = not working.
I always bid on untested stuff from people who's seller history doesn't show video games, these are the people selling their son's console from 20 years ago. I've only been burnt once on an untested auction, but have done well quite a few times. I will admit, most untested and as-is items I buy are games, which have less chance for failure.