Haven't heard of them. I'll have to give them a try.
Also, if anyone here is interested in learning more about/debating over anarcho-capitalism, I would suggest visting the Anti-State forums at
http://anti-state.com/. You may post as a guest without registering, and yes, there are a few critics who regularly visit. All that is asked is that you keep your posts in the Newbie/Antagonist board.
This thread has kinda devolved from it's purpose and I'd rather not flood I-Mock with discussions on market anarchism.
Edit: As an afterthought, you might want to check out the forum just to see more of the criticisms of the theory.