Objective stimuli create subjective experiences inside our skulls. What someone finds to sound "real", "natural", and "disappear", another finds to stick out as colored and snap them out of the state of flow - just think of the feud between magico and Wilson fans both of whom use live music as a reference but come to different conclusions.
Also, our tastes in music, other components we already have in the system, and our rooms all differ. Furthermore, design and technology of some (especially hard-to-drive) speakers will respond better to tubes or solid state. No matter the hype, no reference amp will beat out another on all criteria and in all situations ...
There is no BEST out there! (Despite monthly claims from "audio journalists"/ marketing representatives.
With technology and subjective disclaimers out of the way, on a personal level, I have listened to A LOT of AMPLIFIERS in my life. I have F*ED up my back, cut my fingers, slashed my forearms, crushed my finger nails, smashed my shins, so many times, I can't count them. In late night sessions , I have even tripped over amps and have broken my toes several times.
What I find is that the newest SS like solution, and the like have more resolution than these amps, something like spectral may be a tad faster, but hard core tube lovers would never consider them. Honest tube lovers would find these newer ss creations better than the older ss stuff. Yet relatively speaking, tube guys would still reject these new ss designs as analytical, harsh, and thread bare. "Features" such as a slight speed improvement or more resolution are not noticeable during a state of musical bliss...
Yet If you crave the experience of RICH TONALITY, and flow of tubes, but like the power and speed of solid state, a rich midbass that makes a baritone saxophone and the like sound like itself, you will be hard pressed to find something that beats these amps.
So if your speakers require a lot of power and you need to have SS, yet you value and find realism in harmonic integrity and continuous flow of music, give these amps a listen. No, they are not the BEST, but you may find them as BEST for you.