What people do on their own time is their business, especially if it doesn't affect others, such as their customers. That said, I wouldn't rely too much on the intelligence of anyone quite so willing to *advertise* their illegal activities.
Here is an inquiry on Arrin Dilbeck. You don't have to bother reading it. No one responded. The inquiry was posted by Jason Brennan, who posts pretty regularly here, so you might want to ask him if he decided to order from them or if he had any correspondence with them.
I also did a search on his user name and all posts made by Mr. Dilbeck are in the For Sale forums, so surely he must have some buyers. It may be easiest for you to ask him directly for references and then follow up on them.