I have the same car, the indy version. I upgraded my exhaust to flowmasters and only swapped the air filter for a K&N. Unless you can get into the computer, you best be careful with those upgrades, the car wants to upshift early now. I lost MPG in town but it's still pretty good on the highway.
Anyway, at 66k I had to change the tires. I bought the same ones that were OEM on tirerack.com. They really are decent tires for that car.