John,
I totally understand what you're getting at. Your analogy about the Ford Mustangs is a great way of describing your point. Same name on the cars but "totally" re-designed over the years. And you're right, the only thing the Mustang II has in common with it's predecessors is the name. It does look like a glorified Pinto.
But your right, the Quest line basically all shared the same look with the Quest Z and later the reQuest using newer technology. But once the Odyssey and Prodigy made the scene, their designs were radically different. So I see what your saying, a certain size and style of ML has a different name. And once a new design comes out it's a totally different speaker that only has the "Martin Logan" name and electrostatic heritage in common. But like you, I'm curious as to which ML model was the successor to the reQuest?
Was it the Prodigy? Hmm interesting. I know that the Aerius i was replaced with the Aeon and Aeon i.
Now with the introduction of the Vista and Summit, their styles are once again totally re-designed. The new Summits don't look anything like the Prodigy, and the Vista doesn't look anything like the Odyssey. If at some point Martin Logan does release a model with as large of a stat panel as the reQuest, but utilizing their new XStat technology and built in powered subs, I wonder how radically different they would look?
Seth