If you can prove that they received the item then you are good, but if you didn't go with delivery confirmation then you lose if they choose to say that they didn't get the item.

Im my opinion the customer just wants their item shipped soon, a little note saying thanks is not gonna make them happy. Get it shipped out quick, pack it right. Assume your gonna get a few jerks here and there that are not happy no matter what you do.

I had a ton of problems with Italy, things never got there, they allways got lost, or stolen. Recently the last 4 to 5 items have arrived no problem.