There are some small but annoying issues. My phone is Z10 STL100-2, various version s from very old to 10.0.0.90 through 10.0.1.xxx.; Operator is Beeline, Russian locale.
Phone numbers like 064601 (common short operator numbers in Russia) could not be fetched from sms for callback
Deleting a downloaded file in a browser does not remove it from downloads folder (10.0.0.90; didn't check with later versions)
Either a translation bug or some interface bug in SMS: 'Закрыть этот чат' ('Close this chat') in SMS thread is perceived as 'exit from this chat', but actually leads to a deletion of a chat. In Russian it should read 'Удалить беседу' ('Delete this chat') instead.
Sim unlock and device unlock - sometimes couldn't enter password because of no focus: keyboard is present, but no entry to the passcode field
Sometimes, on device rotation the on-screen picture is squeezed withouth change instead of redraw.