^^...agree with your comments, except that the 4.6iS is 'refined and reserved'. It's quite the opposite actually. In my experience with both, the most significant difference between the two, is the 4.8iS has a lower threshold before electronics reign in. The air ride as well...altogether make the 4.8iS much more refined than it's predecessor. In the end, i went back to the 4.6iS as i like my sports cars unrefined.

OP, to answer your question, no. $7k difference is difficult to justify. However, if you're keen on performance, you could leverage that $7k into 4.6iS mods that will equal the new TT V8...as you mentioned, def' get a feel for both. Just be sure to continue your due diligence on these machines.

Happy hunting