I have the 50 planar and c-sonnar, using them on film and digi M-bodies. I\'ll have to look thru my files for samples, will try to post later. The sonnar has especially nice bokeh from f2.8-f4, while the planar is excellent wide open, and really at any aperture. The planar is usually on my film M with delta 100, the sonnar on my M9 for lower light and people shooting.
When I want consistency I prefer the planar. But I shoot the sonnar 80% of the time
