If you look at the design closely, you will see that it directly addresses the major weakness of the stock system, center relay rod rotation.
The relay rod wears quickly when the Xterra is lifted because the tie rods push upward on it. The pitman side is a ball joint, and allows the relay rod some rotation, this causes the idler side (which is not a ball joint, but a spindle) to wear its bushing.

CALMINI has addressed this problem by attaching the tierod directly to the idler and pitman arm, and letting the center relay rod do only what it should be doing, keeping the two arms in phase.

It's simple and brilliant (and priced right).