I cannot speak for the Agfa camera, I've never laid hands on one. My understanding is that it is very good, but the wind mechanism can cause very serious issues if not in good order.
I have a Certo Six.
Good stuff:
-The best thing about the camera is the lens.
-The wind mechanism is extremely crude, but it works reliably on mine.
-The focus mechanism is one that moves the lens up and down as well as in and out which really provides some parallax correction.
-This is a hard, very rugged camera.
-Focus is a lever (maybe good, maybe bad)
Bad Stuff:
-The camera was manufactured with a rangefinder that used front surface, silver coated mirrors that corroded over time. These must be replaced.
-The rangefinder is very squinty
-The camera cannot be closed when the shutter is cocked.
-focus is a lever (maybe good, maybe bad)
-Very rare.
I really like this camera. I'll not get rid of it.