The difference between the Rolleicord and the Rolleiflex was not in quality of construction but was in number of features.
The Rolleiflex wind on lever which also cocks the shutter was a feature intended for faster, more convenient handling than the Rolliecord's separate wind on knob and shutter cocking lever. However, it is also something else to go wrong.
Although David does not like the combined shutter cocking/tripping lever, I don't have a problem with it using it hand held and if you use a cable release with it on a tripod, it is irrelevant.
The only other major difference is that the Rolleiflex has rotary controls for shutter speed and aperture whereas the Rolleicord has levers.
A later Rolleicord with a Schneider lens will produce results which all but the most critical eye would see as identical to the Rolleiflex.
If you were to get a Rolleicord, I don't think you will be disappointed. Mine is my most used camera.