THE DUST SHOE HAS STIFF BRISTLES, IS THERE PROBLEM WITH MOVING Z-AXIS DOWN SINCE BRISTLES PUSH AXIS SIDEWAYS

A couple things to consider, the machine is most likely moving sideways, so the bristles won't be a problem. The lead screw has a very hight mechanical advantage and the bristles don't pose an issue with this. We have not found that the bristles cause any appreciable deflection to the work we do in our shop; however, you can change the brush for a more pliable plastic, or reduce the number of bristles by selectively pruning.