You're good to go with that Yammie for the M5s.

Regarding v5, I think Axiom has gone about as far as it can in squeezing out performance from their current drivers and crossovers. I can't imagine a v5 without new drivers.

Axiom will be introducing fully active versions for all their speakers. I'd expect improved imaging, improved sensitivity and improved soundstage. Already the v4 is amazing so I can't imagine how much better it can possibly get.