Advantages: Withdrawal of money is possible only when a decent amount is accumulated. Disadvantages: Registration is not as easy as it seems, first you need to be interviewed and only then maybe take it. Comments: For me it is not very convenient that you have to make an initial investment. But for America it's not an exception, it's more of a rule. That is why I got what I expected. It's very simple with mailing lists, if you don't want to get them you won't get them. Most sites provide the same opportunity. I find it much more convenient to work through social networks.