As a seller I'm meticulous with photos and description. I don't offer returns, but of course I would honor eBay's guarantee and take a return if I misrepresented something. I've never had to do that so far.
As a buyer, I usually base purchase decisions solely off photos and completely ignore titles and descriptions, as they are frequently incorrect. The only time I used the guarantee to force a refund was when a seller provided me an incorrect answer to a question I asked about the item that significantly impacted value. After that experience, I always just ask for more photos instead of written answers to avoid putting me or a seller in that kind of position again.