Circuit that sounds good or not is very tricky, some 0.1%THD just "better" than 0.0001% , and similar like slew rate 10V/uS "better" than 1000V/uS...
IMHO, just like Chinese said "THIN woman is beautiful in HAN Dynasty, but FAT woman is more beatiful in TAN Dynasty", there is no fixed standard. Only the Audio measurements still have some problems about "GOOD" sound, they are just too complicate when several freqs come in together at the same time, how can machines test their THD.
Some expensive components may have good material quality, but garanty have good sound? I'm not so sure! My new Pre-amp if take away with the input cascode DN3545 (Pure for +/- 60V needs), only 3 normal FETs, and my DB-01 designed 15years ago use more than 30 of all kinds FETs and BJTs, butwhen I asked my customers about the sound, they all said with HOLCO resistors' version EU-01 is "much" better than DB-01 with PHILIHS resistors.
Seeing is believing!
But now I think maybe the new one with 4 FETs maybe sounds more like TUBE, and more "LIVE", but it should have more distortion than the 0.001%-OLD one!
Hearing is believing?
The sounds more like TUBE, which means the sound is a mess, and the distortion is serious?
In Taiwan, there is an old predecessor, Tsai Kexin (蔡克信). He is 70 years old. I am seriously to suspect that his hearing has gone wrong. Maybe he is very good when he is young.