Rob,
My car came from SPF with 15" wheels with a choice of tires. I selected Dunlop GT Qualifiers 295/50/15 rear, and 255/50/15 front. These were the biggest I could get with what I considered to be the right compound for hot weather driving. I will eventually buy the 17" wheels, and the biggest and best upgraded tires I can get at that time. I agree with "Lew The Tax Man" in his selection of Michelin Pilot series for the best available at this time. I love the Bridgestone SO2's but they don't make them wide enough for me and the 17"wheels. Good luck, and keep us posted with your decision.
Happy Trails,
TL