I'll tell you this. I simply cannot get enough of my M5s. They are like a drug. Yeah my M100s are terrific but at a third of the price, the M5s are 99% of the way there. I too really like the aluminum drivers and in general the very robust design of Axioms. Anyone with Ti or v2 should make the change. As for me, I don't know but I'll tell you the new tweeter is very sweet.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated