Zu, Klipsch, Coincident... All very different,
Definitely very very different. I tried a pair of Zu Definitions in three different systems in my own home for a week and heard them again in two other friend's systems. Absolutely hated them, including with my SET amps. Klipsch from the Heritage line would be great, but the best versions of those are very large and require quite a bit of tweaking to sound their best (much direct experience there as well). Once honed in they can sound magical with SET - if you have the space to make them shine, and a bit of extra time and willingness/ability too, that's a brilliant combination if you don't mind the retro look. Coincidents are great right out of the box with nothing to do but proper positioning. I tried finding a conventional dynamic driver speaker that would satisfy me after years with the lightening fast horns on my Klipsch LaScalas (heavily modified). Coincident is where my search ended - not quite as quick as horns, but mighty close and certainly of the fastest dynamic speakers I've heard in the high-sensitivity realms. Disappear like monitors, and also do very will with SS if you choose to switch (at least the model I use does - not sure about the Victory line as the tweets are radically different). I so don't get why anyone would like Zu though, at least the Definitions...just my own experience with them. Bottom line - try to listen to some of the options yourself and see how they occur to your ears.