I've been selling on eBay for about two and half years, with 100% pos. feedback. So far I have had a couple of disputes that were decided in my favor (knock on wood).
These days I will not ship to Spain, Italy, or Portugal unless it's EMSI - That may kill a few sales, but several Italian customers prefer it - with its tracking, insurance, and delivery in a few days (depending on their customs).
A list of good vs bad sellers will prove a huge task I think. And, if you check a sellers feedback list (all feedback) on eBay, you can tell if they are safe to deal with.