Does anybody have experience with any of the anti-z-wobble solutions for the i3v?

Things like: http://www.thingiverse.com/thing:795954

I find myself wondering, given what seems the rather limited engagement a z nut has with a z rod, that even two of them have limited mechanical stabilizing ability.

If I were to try it, it seems to be that I would want to use one of the "with spring" solutions, not only to help insure the bottom nut stays in place, but perhaps to promote positive engagement of both the top and bottom nuts..., limiting potential for rocking within the nut-well, better resisting the rocking forces applied by the rods.

Just trying to get a feel if this one is worth it..., since it requires fairly complete disassembly of the X-carriage et al for installation.

Thoughts?