"... the Zeiss foreman on seeing this camera nicknamed it the "Idiotica." link
Both appear to be "entry level" cameras. They may be fun to run a film through, but I gather neither stimulate much interest in the vintage/collector circles. Some cameras require a film to be loaded and a magic spell cast before they will wind or operate correctly.
The Symbolica's lens (if clean) could be really rather decent, and probably significantly better than the Mamiya's. Don't worry about the scale focussing or metering - just follow the symbols and instructions normally included on a film pack.
I'd be inclined not to bother with the Mamiya and to concentrate on the Zeiss. Please post any interesting images you get from either camera .... Enjoy!