There are some valid discussions to be had. We've tried to have them in a reasonable manner on their Facebook page.
Unfortunately for the most part they don't have (or want) enough information to have any sort of reasonable discussion beyond their immediate point. If you discuss or question them any further they go into their shell, repeat their first point (ignoring anything you've said or asked) or just exit the conversation completely.
One guy even resorted to calling us out as abusive (or something like that? Can't quite remember) and making up facts, when we have done nothing of the sort.