Jeff, so much here for you to read from owners just go through the site, it is a real hands-on education from owners. All speakers from one design to another there are some trade-offs, so panels to Electrostatics, to box speakers, then horns, then to open baffle. All would change the way music is reproduced, they have to they are all different. Having said that the X's series is very efficient so that something you are already used to, they are very dynamic, and fast, something you are used to, they are open sounding, something you are also used to, where they may be better is that they do all of that yet, have low distortion while leaving the body and weight to the music and they have no sonic character, they sound like what they are feed, your own, and even a change in one power cord you will hear it, yet not analytical at all or fatiguing.
Call Clayton team, they can guide you, give them your room size, your taste in music, and how loud you like to play them, I can say they make music sound alive in the room like there are people playing and that takes some doing for any speaker. I can from Electrostatics Quad ESL 63's to the Sapphire M3's, and they are not as efficient as the X series, yet they can do all of the above, the X series would not have been the best choice for my room, per Clayton so I went with the M3's on his advice and it was a home run. You can't go wrong with their suggestion on the model that will work best for you and from what you are coming from. There are things the Quads can do that no speaker can do, yet I am very happy with the M3 Sapphires.
