I have owned the C60 based Supreme S model since 2014. Regrettably I can't compare them to anything as my first audiophile speakers. I saw them on Audiogon, recognized how rare they were, and pounced. I've been trying to sell them so that I can try some new toys but it seems I'm more curiosity prone than average.
What I can say is that they really caught my attention as a mostly headphone listener. I was concerned when jumping into speakers about phase/timing issues, I wanted a single driver for familiarity's sake. I listen to modern music however I focus more on speed than bass. A 10W SEP amplifier I owned was only good for lower volumes(90db peaks) without hard clipping. Right now I have them with a Schiit Ragnarok and while power is fine they are over damped creating a strong lower octave roll-off & thinness to the sound. I've had bass punch with enough visceral impact that it sounded like someone was knocking on the door but that's where my room & equipment tapped out.
They're real strength is their imaging & off-axis response. They've the speed to keep up with all genres of music without blurring the stage. Consistent across amplifiers is a strong center image, vocalists sound dead in center between the speakers neither in front or behind. With the Ragnarok the imaging is small, with more optimal amplifier matches they approach realistic sizing. Happened both with them setup across the long & short wall in my room so long I kept the audio rack out from in between. The flat driver projects a very wide image which eliminates the sweet spot and throws panned sounds 'way over there' but mandates care in where you place your supporting gear. This blessing is also a curse as my room triples as bedroom & home office. That combined with the speaker's lack of feet/spikes and my bumpy wooden floor make them too much a diva for my modest accommodations. I've heard great sound from them but to meet their needs strips budget from my headphone system & leaves my computer desk shoved into the corner. On the other hand they sound good with company over, walking around, laying in bed, sitting, working out, etc. They may demand of your room but you're free to walk around and multitask as you please, the frequency response stays the same. This should all explain why I have them listed for sale 6 months out of the year, and then decide I'd rather keep them for the other 6. Had I the points to compare against I'd tell you how much of this is exclusive to the FALs, I feel that I may just be describing speakers in general.