Anyone looking for a good preamp solution for their Toriis should make sure to check out the Dodd buffer.  Its available in kit form pretty cheaply and sounds damn good with the Torii.  

Compared to running the Torii naked I gain in soundstage width and depth, get a splash more sweetness and resolution and it MAY be a little more dynamic.  

Its just a buffer and has no gain of its own and I recognize the changes I'm experiencing may be just impedance correction rather than what one would experience with an active pre, but two friends suggested it to me--one with a Torii 3 and one with a Mini-Torii, so I'm not alone in liking the pairing.  

http://doddaudio.com/diy.aspx

The single input/single output kit is a laughable $150.  Definitely worth checking out, IMO, though I'm using the full kit.

Was it difficult to build?  What else did you need to build it?  I don't see a case or power supply.

I stand by the things I said the Dodd brings to the equation, but I should mention that I've got a creeping doubt about it raising.  Hard to put a finger on what the issue is, but I feel less of my attention is focused on the music with it in place.

A different tube may be in order, but I need to buy this unit or return it to its owner pretty much now and I'm leaning towards the latter.

Steve Deckert was not kidding when he said the Torii was a difficult amplifier to match a preamp to.  So far Shindo, YS, Dodd and Tubeguru have not been quite 'it' for me...