Sorry for killing off this thread, folks! (Nothing like an old fart rambling ... think: Grampa on the Simpsons.
To make it short -- my pearl & persimmon 7AT will be picked up next week. I've scanned the tirerack.com listings and it looks like those stock Yokohama tires, treadwear rating 180, might only last through the summer if I'm careful. Then I'll go with the only UHPAS that tirerack currently carries for these 18" rims, the Goodyear Eagle F1 All Season with treadwear 420.
If you scan tirerack prices for replacement rubber on the sport package, the 19" rims take treads about an inch wider, front and rear. ONLY "summer treads" are available. The RE050 Pole Positions that come w/ Sport are the best available tire for the Sport rim, but they'll run you about $300. per tire.
Please note: tirerack doesn't stock every tire from every manufacturer, and by the time you're ready to replace, you may have more and better choices. I'm happy that with All Seasons on non-Sport trim, I should still be able to visit New England into late November.