Leo, thanks for the link to the thread over on SH. You have to be really brave, or pretty sure you have a great product to put it out on a public tour with no oversight as to what will be said about it....and obviously, lots of people are loving it.
A couple questions...did you have a design objective with respect to 2nd/3rd harmonic distortion or were you just going for the lowest overall distortion and then final tweaked for sound.
Congrats on the reviews and continued success!