Bump for related question: I have an OEM cast aluminum accumulator piston (1 large sealing ring, 1 small sealing ring) now. Is there a benefit to upgrading to either (a) a billet replacement that has the same # of sealing rings as OEM or (b) a billet replacement that uses 2 large & 2 small rings?

I have no reason to believe there is any problem w/ the OEM cast piston being used now, but want to know if this makes sense to upgrade it while I'll have the pan & valve body off anyway. Thanks - Brad