I have a pair of stereo amplifiers using your 4X  NXv200 modules which were assembled by Mark Houston. I have to say that they are the best amps I ever heard.
 
With experience from a few other amplifiers, yours simply decimate all others. Clarity, soundstage, transparency and speed of bass simply eclipses any other amp that ive heard. They are so crystal clear that they do great justice to my 2 way floorstanders using Scanspeak 18W8531G00 and Vifa tweeter.
 
The amp is dead quiet. I had to strain myself to hear the slightest stirring of noise but it was coming from my hair that was rubbing against the cone of the speaker! I have thrown all my passive components away and set up my active crossover, with each driver independently powered by your modules.
The sound is so natural and filled with emotion that I challenge anyone to feel nothing after listening to them.
 
A truly exceptional module you have designed, Anthony.

Guitar string resonances reveberate with authority! Walls are vibrating though the sub is off. So far this kills my Marantz amp in all aspects; warmth,clarity,soundstage,coherence and speed.
The slightly bright nature of the amp is neutralized by the mellow sounding Vifa tweeter. What emerges is absolute listening pleasure!

Dinesh, Melbourne, Australia