What better way to compare staircase artifacts than with a staircase? Here we see that for classic aliasing artifacts, TPXAA smoothing performance is as good as FXAA. Looking at the grass texture in the upper left corner the undesirable overall blur of the FXAA image is faintly visible.
In this purely 2D comparison, TPXAA does nothing while FXAA deforms the straight red geometric shape and diminishes the text outline.
Finally, this mixed comparison shows sume HUD deformation with FXAA that is prevented by TPXAA.
Full source images: