I've had a bad experience when purchasing an ex-display pair of speakers from a well known seller's website.
The speakers were a pair of Dali bookshelves. The ad said nothing else than "perfect, like new boxed etc" while the photo was unfortunately only a stock photo. I did phone the marketing guy who reassured me again that everything was indistinguishable from new so I didn't fret too much about having seen no pictures. My fault I know, but if a "reputable" seller tells you that all is perfect, well.. :roll:
When I got them and opened them everything seemed alright until I noticed that the brand badge on one of the speakers had been glued upside down. Now, I KNOW it's a meaningless asthetical gitch however:
-this badge is quite large and visible at all times (not covered by grilles)
-I would have appreciated a honest and reputable seller to inform a customer of this sort of things, given that I had asked specifically "are there any imperfections, etc"
-in case I had decided to sell the speakers one day, their resale value would have been smaller than normal - as there are some people who care about these details.
Therefore I decided to return them. Unfortunately, getting my money back was bit of an odyssey. Needless to say, I will never deal with this lot again.
Bottom line, I'd say - just like on ebay, even with ex-display items bought online always DEMAND to see pictures and ask to be specific about the item condition prior to taking your decision.