Your recommendation for the expensive tubing is based off a large build with a very tall Z axis. That Z of yours is compounding any flex several times. A normal-sized 2x2 build with the minimum Z screams through wood. If you look at my speed tests vs yours, since it is the same tubing, you will see how much faster I can cut than you just with a normal sized build. You needed the DOM mainly because of your choice to do an extreme Z. CNC Drag Race, 0:39! - YouTube