I think you have to go to an audio show to hear all of those. Even then, Geddes does not do shows anymore. I have only heard the Amphion, SP Technology, and Emerald Physics CS2. I liked them all but from everything I have read, the Geddes and Audiokinesis are the ones to beat. I like the WG sound so much I built my own clones based on Geddes, AudioKinesis, and Emerald Physics concepts and parts and they are the best speakers I have ever owned. Note the bias alert as everyone favors their own creations.
Nothing against VMPS but these are clearly not in the same category as CD waveguides with their advantages.