There are a number of people on APUG who love both Yashica and Minolta - but I never did! All the cameras you mention have Tessar-type lenses with typical Tessar performance - good micro-contrast, good center definition at full aperture, edges coming in about 3 stops down, corners probably never quite equalling the center even at f22. I found both Yashica and Minolta had fragile shutters and were generally not nearly as robust as a Rollei. The post-war Rolleicords were the result of typical German product management of the time - build a great product at high investment cost, find your selling price is too high, invest yet more money to make the product cheaper. In the case of the Rolleicord, the cost-cutting fell on the film winding (not linked to shutter wind) and the shutter release, which on certain models was a rather horrible "push one way to wind, the other way to fire" affair. Otherwise, I think Rolleicord and Rolleiflex build quality was identical. I never made friends with the built-in meter on a Rollei - you need to angle the camera down and then read the meter at an angle of 90° to the scale, which is hard unless you have a neck like a giraffe!