Another difference is the vent holes in the side of the MKII
I'm using a MKI axe with a MKII MCF and got a cable that is Etherconn on one end, normal jack on the other. I think its the best of both worlds as I have the rugged connection into the MFC, which is what gets stepped on, and then run to a male/male RJ45 connector, which then runs into the Axe, reason being such someone trip over the cable, that little plastic tab is going to break away before it would pull my rack case off the table etc.
With Etherconn on both ends, that cable isn't pulling out, so if someone ran across the stage and tripped on the cable, its either pulling my board, or my Axe across the stage, which would be bad news .