I would say yes, but it doesn't matter what we say/tell, those who don't believe just won't believe.., one of their simple but illogical logic based reason/rational is that if all amps (even though almost no one has actually ever said all amps sound the same, but that's why they have in their mind) sound the same, why are there so many and so many who don't mind paying a lot more for those they think sound better. In that sense, no, it is not a "solved" problem, not until amps are sell with certified transparent result based on not only bench test results such as ASR's, but also DBT based results, certified engineer's report, and better still, along with a psychologist's note) lol.....