I´m just curious to know how any ex3 users set brightness and contrast on the display.

There´s nothing like a fixed "medium" or neutral position.

Using the histogram it´s no problem. But how to setup something which visually represents a somehow neutral impression?

Thanks
Holger

Use the cameras colour bars as a reference. Set up the Contrast so you can just see the darkest bars and the brightness so the white bar appears white but not over bright.

And then just tweak it by eye until it seems nice for you. You should really be using zebras to judge exposure, so the viewfinder settings should just be whatever makes the image easiest for you to focus and view. On broadcast cameras the "normal" position tends to be at about 1 o'clock for both contrast and brightness, but all users have their preference, same goes for peaking, some like it cranked right up, some right down and some midway.
Steve

Thanks a lot

Regards
Holger