Yes I am using similar lead screws from the BOM on both HercuLien and Eustathios. I think it comes down to if there is friction between the screw and the nut, it creates a torque when doing fast layer changes. The force likely lowers as it breaks the static friction barrier, so this changing rotational friction based on the right hand rule translates to a horizontal force into the linear guide rails and bearings. The guide rail and bearing are of course not perfectly ridged, so they create minor variations.
Long story short ball screws are better than lead screws for fast layer changes because there is little to no static friction to overcome, so a much lower moment induced horizontally. I.E. I am jealous of the fact that you have ball screws