The JC-2 clone is ok for the money, it's a bit veiled but run close to max rail voltage it sounds 'nice'. JC designed it for pro audio line duty, do you really need all that gain? 6V is way too much for domestic audio, it drove my test speakers by itself to a point where i got shouted at to 'turn that dam thing down'. I had to attenuate most of that gain out in my system.
I replaced it with a DCB-1 which is much more transparent but still great value for money.
Don't think that is what he designed it "for".
But you can just ask him, since John Curl is on here just about every day.
With my little experience, passive are never so good with soundstage and when the volume varries !
I prefer an active quiet one , even if unity gain...
I also believe good passive are above my budget.
He's on my friends list, it was him who told the story of it's development, the first version was used in the pa system for the grateful dead if i remember correctly. There is a thread on here somewhere, search JC 2 clone and it's in one of them, there are several. Or ask him yourself.