I've reported that some of mine arrived broken in and others did not. Some required a few hours and others tens of hours. I've also reported that I was noticing significant "voicing" changes with temperature changes in my v2. I don't hear that in any v4.
Interestingly enough, I pointed out to Ian that when Soundstage measured the M5, they found the impedance curve to be quite different up top from what Axiom published. He surmised that could be the viscosity of the ferrofluid. They may have tested it when the speaker came in from the cold. That could explain why I was hearing differences in the v2. The v2 and v4 tweeter designs are of course different.
