I bought a new Olympus OMD E-M1 (recently after my PEN got broken). Such a precious peace of technology with high-end image quality! I really love this tiny monster! I used it already for a wedding-shooting and on my (still on-going) three-weeks trip Stockholm. And during the latter one it happened: Problems with the rear-wheel occurred.
I operate my cameras mostly in manual-mode (M) and the rear-wheel of the E-M1 is used to adjust the exposure time. On the street I have to adjust the exposure time very often and very quickly, while I keep the aperture mostly wide opened. A wheel, that works inconsistently, slows me down and I miss important, unique moments. And that's the problem I have with the E-M1: adjusting the wheel has often no effect on the exposure time or any other setting related to that wheel. This issue is well documented by other OMD-user on DPReview.
When I'm back I'll bring the camera to my retailer. Since this problem seems to occur from the very beginning of the E-M1 (since 2013!), one might ask the question, if Olympus is taking its quality control seriously. The E-M1 is a high-end premium product. I'm totally disappointed.