i think onecoin might even be more scammy than avalon
Onecoin is definitely scammier than any of the companies that the OP mentioned since people cant exchange their coins for fiat whenever they want to. OneCoin executives and top MLM promoters claim that you can make 1,000%+ in 2 years or something though not half the money you put into the company will make it out within those couple of years of enrollment.
I have a friend who keeps on insisting me to join under him in Onecoin and it makes sense that it is a MLM scam. I didn't want to tell it to him except I'm telling that I don't have money to invest on him. Maybe its time for me to really exposed to him that it is indeed a scam that is why I don't what to join with him.