I don't know if I would worry too much about the Corporation of Flight guys -- they struck me as being even less substantial than Moller/Freedom Motors.
At least Moller/Freedom Motors can be associated with something that exists in the non virtual world.
Besides, Moller's entire modus operandi is the Rotapower Engine. If they even consider using something else, it's a tacit admission that they've been wasting their time for the past 30 years or so.