I haven't personally used any of the bows you list, but I have used similar ones. Almost all bows such as these are made in China, and will generally have pretty good quality for the price. It is true that given China's weak or nonexistent patent laws, once a bow becomes popular it will be copied by other companies.
In general, the first thing that you will notice on switching from the bows you are used to to a 68” or 70” longbow is a considerable reduction in arrow speed. In order to retain close to the same arrow speed as a recurve, you need to select a 62-64” longbow that has reflex deflexed limbs. There are specially designed longbows that are even shorter than that that will outperform recurves in some cases, but those are custom designed and out of your price range.
Of course, many people choose to shoot the longer straight limbed longbows as a personal preference, accepting the limitations of that design.
It is somewhat difficult to switch back and forth between long straight limbed longbows and shorter recurves, due to differences in grip style, center cut, and performance. I would recommend starting with one of those you have listed, and not upgrading initially to a slightly more expensive model. After shooting one for a while, if you like the style, consider upgrading to a $400-$500 custom longnow instead.