The Technikardan has more flexible movements, so it can work easily as a studio camera for still life, for architectural subjects, with wide lenses, and it folds compactly, so it works in the field as well. Jack Dykinga uses a Technikardan.
The Technika offers the attraction of a rangefinder, so it works as a press camera or for portraits in the studio (so you can focus with a filmholder ready to shoot), and it is self-casing, so it's more protected in the field than a Technikardan. It has back movements and generally very good movements, so there is little view camera work you couldn't do with a Technika, but you might have to think about it a little more than you would with a monorail. You have rear swing and tilt, front rise, shift, swing and tilt. So if you need front drop, you might turn the camera sideways, rotate the back, and use the front shift for front drop or you might mount the camera upside down (which is easy to do) and the rise becomes fall. If you are shooting a still life and need to keep the lens in a certain place and want rear shift, you need to move the camera and use front shift. Wide lenses are a bit awkward with a Technika, compared to a monorail, but if you don't need the rangefinder, the Tech 2000 and 3000 work better with wide lenses. John Sexton uses a Technika.