I've been thinking Mesh Levelling is the ultimate, in the way it compensates for all kinds of tilt and sag. But having done a little reading it seems to have definite downsides: in particular that any deformation is copied right through the part. So best not have any sagging rods. 1) Lots of people have been upgrading bearings. But did anyone consider upgrading the Y-axis rods to, say, 10mm? They don't move anywhere so it wouldn't slow anything down, but it would reduce curvature. 2) The weight reduction possibilities with Titan / pancake motors are really exciting. Is there any possibility of swapping the hefty X-axis motor for something geared and pancake-like? (Mostly for the sake of speed / acceleration.) 3) To what extent does movement in the X axis rods come from flex in their mountings? Would carbon-fibering them make any difference?