Until my cheapo HF magnetic base broke I got about 0.0015" backlash on Y and 0.001" on X. I used MDI and went in 0.10" increments back to zero and then to 0.750" in one large step and back to zero. I saw 0.003" one time but the magnetic base was starting to slip right before it broke. The first few readings seemed repeatable. Nate is sending me some new spindles and belts so I'll get those on soon and test it again. In the meantime I need to either buy another magnetic base or go into DIY mode, likely the latter.
David