I have never heard of any of those guys, other than Jennifer Laycock from Search Engine Guide. Personally, I am always dubious about any Internet Marketing certification courses, because these is no officially recognized certification course for anything related to Internet Marketing, other than perhaps the PPC certifications offered by Google and some other search engines.
The courses may be good, but the value of the certification won't buy you a cup of coffee.
I will check into Todd Malicoat. I don't know who he is, but if you think he is good, I believe you.
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin