This article compares the sharpness of the Olympus M.Zuiko 25mm 1:1.8 and the Panasonic Lumix G 1.7/20mm. I am currently working on a full comparison review.
All pictures were taken with an Olympus OM-D E-M10. I used a tripod, the 0 sek. anti-shock setting, a remote release and turned the stabilization off. I also took several pictures for the image center and the image border for every aperture and selected the sharpest to make sure that the result was not affected by focusing errors or other external factors (f.e. vibrations).