Which new Audi is best, and why?

[jzwahlen at cerrejon.com]

In the near future I may be in the market for a new Audi.
Under consideration are:

A6 4.2 V8
A6 2.7T
allroad quattro
S4

Looking for a sedan, primarily for my wife, therefore it
will most likely require the Tiptronic tranny.

Can anybody give me their opinion, on this list, are you
kidding ;) ?  I am particularly interested in their
comparative ride and handling characteristics.  Does the
allroad ride rough or have excessive tire noise?  I know
they have specially designed tires for this car exclusively.

Any comments might help.

jazman

1999 VW Polo Classic 1.6L
1994 Porsche 968

formerly:
1993 Audi 100CS
1987 5000CS TQ
1985 5000S
1982 GMC S-15 (sorry about that one folks)
1978 VW Rabbit
1971 Plymouth Duster =8^0
1969 VW Beetle