Audible illusions Modulus 3A or Klyne 6L

a hot rodded modded out Audible Illusions Modulus 2D would smoke em all...
or look for a Klyne series 7... the best.

Bigtee,
When purchasing a unit at the level an AI3, you should not have to be advised not to put NOS tubes in it, period ! That is the main reason why AI units loose so much of their value after only a few years when purchased new.

That's unfortunate because they are fine sounding machines.Like you said,if someone does'nt care about anything but tank built tubes to go with it,fine ! But .... Have a look at this:
http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html

I have owned the AI M3 and now the L2. Amazing pre's. Bests my Rowland Concerto in quite a number of ways. As far a quality, never had any problems.

The Klyne can be matched to every amp based on its Gain Potis.
And it is reliable/good sounding.

you just missed the CAT preamp to name three of the mose regarded, sensible choices of preamps - I am sure any of them will match with your described setup with no issues.