Hi Alex: I don't know the difference. The only real questions is whether the Amazonas is a knock off of the real Byer of ME model (explained above in thread). The photos are stock and taken too far away, so one would not know until it arrived at their home. For $50 more, and the guarantee of the proper product (including the two-year full warranty, the human being that answers the telephone in Maine, etc.), I'd always pop for the real thing for a product like this that I would be using for a decade or more.
But to answer your good question, without seeing it, no one can be sure (and the shipping weight is onerous and you will not be able to pay and have either the counterfeit or the real one shipped back/returned, so there's no way you can "test drive" one, unfortunately, to find out).
I use my two Byer of Maine Vario original stands daily still. Sweet. Good of you to look into this brand, AlexM.