The current cap people are throwing around for A8S for melee dps hitting the front is 698-700. That link that was first thrown out is outdated and confirmed inaccurate - it was a bogus estimation someone made early on in Midas.

A5S is like 660-something, A6S is 670-something (675-676?), A8S is 698-700. Because of how gear works this tier, you wanna just build for the A8S cap and sit there for all of it, so the other turns don't really matter much.

It's a trade-off of ~30 secondaries, which is a negligibly tiny amount of effective damage for a potentially large investment of additional g5 materia.