We try hard to bring on guests that have a modicum of integrity.  The only time we don't do this is if we have no foreknowledge of the persons integrity.  I prefer to know nothing about a guest before I have them on as once I learn about how dishonest or irrational some of the theist guests can be, I tend to lose interest.  We know too much about both of the people you mention, they are the laughing stock of the atheistic community.  Someone suggested last night, "maybe you should have them on and just embarass the heck out of them."  My response, "If we had them on, we'd be embarrasing ourselves."  The guy who goes by "atheism sucks" was recently outed as mentally insane, he now has a blog impersonating a member of the RRS in which he has conversations with himself from multiple accounts, and uses the fake profile to comment on his own blog as well.  This sort of person doesn't warrant time on our show, he warrants time in a court of law.

 This isn't to say that it'll never happen, however we have so many theists willing to come on the show, that we don't know the ins and outs of, that we're looking at those people as candidates.  We're most interested in Pastors, Priests, and Christian radio hosts to satisfy a need of "knowledgeable" Christians on the shows.  

We could debate whether JP best fits the category of Crazy, Ignorant, or Lying... or he's such a conglomeration of all three that it's impossible to choose.

Holding is incompetent. Theists would be wise to avoid his arguments.