It's "based on block chain technology". Vague terms and marketing with no elaboration. Requires you to create an account. No information on what payment methods are accepted before creating an account. They say that they can and will take down accounts if they break ToS but this in direct contradiction to their own previous marketing which states "no logs". High cost unless you go for a long-term lock-in contract.

There are other things but there are the main ones.

2/2