I have shipped more than about 1200 items without traking number in Japan, packages have never lost. Also about shipped out 2060 packages to out of Japan. Some people are complaning Japan post in the country such as the US though, After once your package is in the US, its actually under the controle by receiver's country post such as USPS.
The glass arrived to me very safety, It didn't have bad thing happen,such as damaged or lost or cracked. I thought it would be damaged cos I sew many bad review in listing. Thank god, my glass was just find:)Thank you Japan Post!