Someone mentioned to me in fleet chat the other day that he thought abilities from BO's don't necessarily stack, and that there is a hard cap to how high things can go.

So I'm curious to know if they stack and how high the cap is (if there is one)?

I have a borg BO with Efficient, a saurian BO with Efficient and a human BO with Leadership (space version: grants 15% faster damage and subsystem repair). I'd love to know how many more Efficient or Leadership BO's I can stack before spending 35-40 million EC