Temperament Question

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Keith writes:
<<  I'd like to tune her piano in a temperament in
which she will be able to hear as much just intonation as possible. I have
Jorgensen's book, and have been looking at the Pietro Aaron temperament,
which has a lot of just thirds, but no just fifths; and the Kirnberger
which has some just triads. Question: which temperament has the most just
intervals, or which temperament do you think will give my customer the best
experience of just temperament. >>

Greetings, 
    The "Just Intonation" is not a definitive term.  You can tune all the 
fifths perfect, (except the last one) and have "JI".  Of course, the thirds 
will be screaming.  You can tune eight out of 12 thirds Just, you must decide 
which ones.  The acoustical fact with 12 note octaves is that fifths and 
thirds will be in opposition.  Help one, damage the other! 
   To stay in the traditional temperaments, the Kirnberger II give several 
Just thirds and fifths, but there is a lot of tempering in there.  
I would use the Kirnberger, since there will be a lot of string movement 
required to reach a Aaron 1/4 comma tuning, and it is hard on the piano's 
stability. 
Good luck, 
Ed Foote