Can somebody let me know which one is more active?? And I wanted to start a Lvl 9. Lld

Are they common?? Like will I find very many duels or what Level is the most common??
Please help

lvl 30 non ladder would be ur best bet
lvl 30 ladder would be ur 2nd best bet

that being said i also do lvl 9 so ill give u duels if u make a 9 on nl