This thread seems to imply that there are only two options: coded 9s/10s or "standard". There are quite a lot of other options, some of which the Eastern Europeans like to play.
What to me is clear is that your opening leads against suit contracts should be completely different to those against NT; and possibly the level of the contract matters as well.
You should also have different agreements if partner has bid the suit, depending on how partner has bid the suit, and if you have raised or not raised during the auction. For example, against a suit contract I usually lead the 'standard' 10 from K109 or Q109 to length, but if I have shown length in the suit and partner has raised, I lead strict 3rd & 5th (9 from K109xxx, the lowest from K109xx) because count can be vital.
Defensive carding in general seems to be something that is very regionalised round the world.
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I thought that the use of odd/even first discards was nearly universal among experts. At least, that is my experience.
In England, odd/even is virtually unknown amongst the good players and reasonably common among bad players. In Italy, absolutely everyone plays it (to the extent that if you ask an Italian what discards they play that's what the answer "standard" or "normal" means).