Never, ever buy tickets off eBay. I don't care if the guy has thousands of feedback - it's not a good idea, and much of the time tickets go for more than or at least close to what they are actually worth making it not worth the risk.
It's just not safe - what if they guy got a batch of bad tickets and sends you them by mistake? What if he decides to go out of business and ends up intentionally sending bad tickets, not caring about bad feedback since he's not selling anymore?
There are just too many "what if's" - and I know that unless I was going solo and didn't care, I wouldn't want to be at the gates of the happiest place on earth and sent away becuase I had a bad ticket. I can't imagine how it would feel for that to happen to a family - especially since they may not have the hundreds, or even thousands, or dollars to replace them on the spot.
eBay = good for tangible goods, eBay = bad for services and tickets
In any case, it's illegal to resell themepark tickets, and with Disney's new signature and bio-metrics hopefully the eBay market will die as the "old" tickets phase out.
N.E.D.
I don't know that I would buy from ebay again, but I am ok with this purchase, I did my research beforehand and knew exactly what I was buying, and if they don't work, I'll have paypal to back me up.
So someone is going to get upset about this when they get to the gate and their fingerscans doesn't match.
Imagine the horror of realizing you just spent hundreds of dollars on worthless pieces of paper. 
