Simon,
In principle an easy question but very difficult in practice as you know!
In my shortlist would be the 911 Turbo (997 Gen 2 PDK), RS6 (5.0 V10) and 612 Scaglietti.
Would plump for the 911 with the same rationale as you.
Regards,
Robert
P.S. What do you think of this?
599 GTO 
