i tried a set of clayton’s m3 sapphires, i felt the open baffle design is a real winner, providing great sense of space and realism in the bass - very very impressive in that regard
as much as i wanted to love them, keep them, i could not get accustomed to their rather forward treble (despite much much effort expended to ameliorate) and relatively recessed midrange, but those issues are ones of tonal balance, related to driver selection/mating, and not related to the wonderful open baffle nature of the design
i think many other users have had really great results using good tube amps with spatials (which i did not want to do in this case for my own reasons)

