Originally Posted by Sċm
Cass has a higher skill cap, but if played well, outclass kennen anyday.
It depends what you mean by "out class." I agree with Cass having higher skill cap. In lane and brief skirmishes, Cass is definitely better. Very high bases and kite ability.
But in team fights? A highly skilled Kennen will beat a highly skilled Cass any day. Cass's hard cc is conditional and she is very susceptible to characters with dash and hard cc (such as Riven or Panth). Kennen's ult is not as conditional and his damage and cc persists even if he is stunned. That's provided you get the ult off.
In any case, both good choices.