I've read and heard folks say that they believe the Levinson stacked Quad 57's with the ribbon tweeters to be better sounding than Soundlabs. I cannot make that claim myself, I just wanted to put that out there.
My conversations in the past regarding Soundlabs were relevant to the overall build quality of their speakers. I cannot understand why Quad hasn't seen Soundlabs as a guiding example in how to build an electrostatic speaker correctly.
A friend of mine is currently building the Levinson 57 stacks, so I wait with anticipation to hear them once they're finished.