205/50-15 is the size to go with like everybody said.

However I'd be a little wary of the S-03s if you're looking to get 30k miles out of em. What Spec R is talking about is the tires' ability to maintain more of their wet traction as they wear. They do not actually get stickier as they wear down, and their treadwear rating is low enough that they will not last as long as you want. They're still an awesome tire though.

If you want something that lasts for 30k miles I would suggest the Bridgestone RE750 or Yokohama AVS ES100 in 205/50-15. They're not the absolute stickiest tires out there but they are both very good tires and will last longer than the upper eschelon (in terms of traction) tires.