In my opinion, a review should detail what happened. It often happens that a customer has unreasonable expectations, misinterprets what the host's obligations are, refuses to take responsibility for his own actions (such as agreeing to a TOS only to denounce it now that a clause has come to affect him).
Simply saying "they suck and they're a scam" doesn't prove anything, it's just a personal interpretation of facts. It is, in a way, like a vote in election: just because you vote for X, it doesn't mean he's necessarily better than Y.
