For me, it would be about 150 grains.
However, I've noticed that many people send in responses to similar questions recommending much weaker dynamic spines than I do. For example, it wouldn't surprise me if someone recommends 200 grains or more.
I have to assume that the way people shoot the bow is different enough that different people tune similar setups and get different results, so the only thing that is really going to be meaningful is if you do bare shaft testing and see what flies best for you.