I supported a project which failed - which is not a bad thing, that can happen. But you don't get your money back (now it's six months later), that's bad.
Ali Baba is a platform for sellers and not for buyers. If anything goes wrong Ali Baba believes what the seller is saying and they ask you as a buyer for proof. Why shouldn't the seller proof that he is right? So for me Ali Baba is bad experience with the chance of being scammed any moment.