Well I have a completely different system now and a new house, and I'm gonna be completing a tube based system end of month.
But as far as the JC1+ go... I have them paired with my Focal Sopra No.3 in a large (18'x52') room.
As for the JC5 vs JC1+... I'm of the opinion now that it's all about your speakers, room size and listening habits.
If you have 90+db 8ohm speakers, listen at moderate sound levels, and have a small room, then JC5 would be all you need (95+% what the JC1+ offer for half the price).
However if you have hard to drive speakers, and want the most out of them then JC1+.
If I had my Sopra 3's with the JC5 I would just stayed put, I have 80 class A tube watts powering my Sopra's and they sound amazing, but again I have the Mola Mola Tambaqui now so that too changes things.
All and all... I really would say JC5's and spending the difference in price on the Tambaqui would bring more audio nirvana then the JC1+ alone.