I'm in regional NSW and interstate buyers, especially Tas, WA and far north Qld, I always send a message saying it could take X weeks to arrive, longer than what the eBay estimate is. I also point out their item will probably arrive much sooner, but just warning them that it could be slow. So far, have not had any problems. Twice it's taken 4 weeks to get to WA (as is evident by the tracking numbers) which is why I send messages now.