The 3-axis zero plate isn't "old" and the pressure-sensitive Z-zero plate "new"—they have different functions, and I use both. The 3-axis plate can be plugged into the same connector on the gantry that the normal Z-zero plate uses, and placed where it is needed for 1-, 2-, or 3-axis zeroing (the software routines are included in SB3). The pressure-sensitive Z-zero plate can also be plugged into that connector, but it makes much more sense to order it with the optional extension cable and permanently mount it somewhere on the table where the spindle can reach it but it won't be in the way of normal operations. It is then wired directly into the control box. The point of the pressure-sensitive plate is that it allows you to use a routine that automatically adjusts the Z-zero after a bit change. That's convenient for normal work, and almost essential if you have an automatic tool changer (which I don't).