While you could go looking for trouble, why not do what CNET did?
I was late to the game on the final days of Panny plasmas and the only ones in stock near me are floor models. I pulled the trigger on an ST60 and am wondering if people have advice for what I should do to confirm that there hasn't been damage done to the screen from the demo that they run on loop endlessly at the store (Sears). Obviously I need to take a look for image retention but I assume that this will be readily apparent. I've also read that improper use can cause issues with evenness of color. Is that true and, if so, what would be a good way to check for the issue? Am I missing anything else?
Right now they are extremely difficult to find (I was looking quite recently). Odds are, there's no damage. It's one the best plasmas ever made. Just verify the full warranty is available, and test the heck out of it when you get home. There's no easy way to do this properly in the store. Verify the return policy for Sears as well. Good luck on this one
Run all sorts of different content, SD & HD, letter boxes and no letter boxes, etc. Blu ray & DVD too if that matters to you. View fast motion content/bright sporting events, dark movies, game systems- the gamut. I'd also suggest trying out different connection type, and test ALL the HDMI ports (and digital optical output, if you ever need it). I would also test the built in speakers if that's an issue for you. And don't forget the USB port if you plan on connecting to external drives for additional digital content. FWIW, malfunctioning wifi functionality can be remedied by simply using an ethernet cable, so test that out as well. Often the floor models have not received the firmware updates, so run those as well ASAP.
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