New Single Piece X-Axis vs. Steel Bar Mod

Has anyone who has gone to the single piece X-Axis extrusion previously used the steel bar mod to stiffen their X-Axis? I am curious if there is a benefit over the steel mod (not in simplicity, but in rigidity).

I already have the steel mod and am just wondering if there is any benefit to getting the single piece extrusion.

A steel reinforced solutions (4x60) is in vertical direction 120% of the one piece solution, in horizontal direction less because the steel in in the center of gravity of the combined beam approx 60%. So a well made steel bar will do just fine.

I too am curious if the single-piece x-axis upgrade offers a significant improvement over the steel bar mod. Has anyone tried both and noticed a difference? I am about to change my 500x1000 X-Carve to a 1000x500 X-carve and now would be the time for making the upgrade. (I already have the original 1000 MS x rails.