See my L-mount mirrorless wishlist
This page looks at performance of the Panasonic 24-105mm f/4 Macro OIS at 24mm on an extremely demanding planar (flat) target at medium distance. This particular subject lays bare all lens weaknesses, but particularly micro contrast across the frame.
Panasonic 24-105mm f/4 Aperture Series @ 24mm: Mosaic
Includes images up to full camera resolution from f/4 through f/8, along with large crops showing the behaviors.