Orangecrush: I had almost the exact same tube compliment and the same fantastic results with Zu Omen Defs w/ HO Drivers paired with the Torii. Do you have the old HO drivers or the new Nano Drivers?
Vocals were amazing, life like and very convincing. In addition the Torii was very fast, quite detailed, and the best amp that I owned in combination with the OmenDefs (and I bought and auditioned many fine and expensive amps). For vocals, it was not quite as good as the Coincident Frankenstein 300's, but in the end I sold the Franks and kept the Torii as it had 99% of the performance in the vocals and was much better with more dynamic and bass heavy music.
However, as we all should know, it's all about synergy! When I sold the Zu's and changed to Pendragons, I could not tame the bass from the Torii And I spent long hours trying to figure it out to no avail. The Torii is very transparent, quite detailed, and definitely will reveal system weaknesses. So if you are in need of more warmth in your system then I would go with a different amp, and if you want to stick with Decware the Mini Torii is on the warmer side of neutral than the Torii.
I can unequivocally say that Zu plus Decware is a fantastic pairing! Now that I have Zu Def Iii's I wish I had the Torii back, though the new Zu drivers are less warm and more detailed than the older drivers, so that may affect the synergy again.