Mark, sorry, missed those questions.
I'm using a Raytheon that shipped with the amp from Steve. I went through a whole box full of 12AU7s I'd collected through the years for use in my EICO, ZBox and DEC685 and there were a lot of possibilities. I really didn't like this Raytheon when I first used it and the ZP3 was new. I had some good hours with an old Mullard that came out of my EICO HF81 and a Telefunken. I was using Raytheons in the 12AX7 positions (bought from Mike [tgarden] when I bought the ZP3) and when the ZP3 was finally broken in I popped that Raytheon from Steve back in, let it cook a while, and it's stayed in ever since. The three Raytheons give the ZP3 a very clear and powerful character.
In the Torii Mk III I've tried all kinds of input tubes and just don't think the 6922/6DJ8 etc. family works for me. I've stuck with a number of 6N1P over the years and like this one best, and have been using them a few years in my Toriis and my CSP2+ preamps.
http://www.cryoset.com/catalog/product_info.php?cPath=21_24&products_id=263&osCs...I'm using JJ 6CA7 tubes as the power tubes. Others have had reliability problems with them, I haven't. I love the sound. I haven't tried the KT66, maybe one day, I still have another set of the cryo'd JJs on the shelf to use this upcoming year. I use early 'fifties coke bottle shapped 5U4G rectifiers, early fifties coke bottle shaped RCA OB3s and RCA OA2 tubes in the other sockets.