Mk2 improvement over Mk1 was a lot more than even I expected and that was with the new copper coil midrange units still not burned in. The XO parts were precooked though. I begged for this because it only takes about a hundred hours for the drivers but over 300 hours for the caps.
The impression is the same from all of us here that did the upgrade. Jim, Manny, Rodney, me and those that have worked with Mk1s and Mk2s in the same spaces, myself and Cor. They really are different speakers even if they look the same and retain some parts. Funny thing is if you actually count the parts retained, the number is tiny. When I posted the picture of the crates containing the new stuff for upgrade, the triple wall reinforcements, complete sets of crossovers, spools of internal wiring, etc. One guy on that forum said just that. That isn't an upgrade, that's a new speaker! I guess they are used to seeing a new tweeter and a few parts in a shoebox. That ain't the VSA way LOL!