Jmcgrogan2 makes an interesting point, when he suggests it's hard to believe that a hybrid could sound like an SET (or visa versa I guess).
Thirty years ago tube amps and solid state amps sounded very different, and they each had their strengths and weaknesses. Over time designers have been working to diminish the weaknesses and improve the strengths, and the result is that solid state and (at least push-pull) tube are becoming more and more comparable, picking up more of the positive traits of the other. Will pure solid state ever be as life-like as tube? I don't know, but it's getting closer.
This may happen even for SET amps. I have personally heard SET amps in recent years that do not have the traditional drawbacks of early SETs - which to my ear were loose bass and rolled highs. We no longer have to make that tradeoff in order to obtain the glorious mids of SETs. Even the power of SET's have increased somewhat, so that we can use a little bit less efficient speakers with them.
Stranger things have happened. Let's be skeptical but open-minded.
Art