They have a habit of mixing small amounts of bitcoins but when you trust them and send large amounts, you get scammed right away. It sad that you got scammed even after warnings by other scammed members had already been put across.
True, they are selectively scamming for a long time. But still people use it. Although a lot of people have warned about it, the problem is almost all the victim is new in this forum and they had not done enough research before sending coins. If they were member of this forum, they would use Chipmixer.