I have always been paid slow by Mystique but I did get paid. Sometimes I would complain in email after email but it would eventually show. I've threatened to never shop again and to call the BBB. Usually my scheduler would respond after that. It was truly ridiculous.
I did one shop in Nov and one in Dec 2013. They paid me the Dec shop quick which was bizarre. So I went to my account to check on the Nov shop and they put it in as paid. I went to my paypal to make sure I wasn't imagining anything and sure enough, there was no payment there for the Nov shop. This was a $50 RibEye's shop. I emailed my scheduler, who normally responds after two emails, and have gotten nothing. I finally started calling and of course get no answer there.
I agree with the above poster, usually this is a sign the business is going bellyup. I have had a company do that to me before so I've seen what it looks like. I'm thinking I should be thankful I got the first $50 and that it is more than it could have been.