While I've never had any problems with sellers on this site, I've gotten pretty fed up with ebay sellers as well as card companies in general. I had an ebay seller try to convince me that overnight shipping did not actually mean overnight and could take several days to ship despite paying $30 for shipping.
All AP's I've purchased directly from artists have been amazing art at an amazing price. Most of the time you get to pick the subject matter and most importantly you get to help support the artists.
Busting boxes and cases was fun for a bit, and I'm excited about my 2 boxes of TWD S2 but I've just decided to buy APs for the most part.