couple of my buddies just picked up a new set of michelins, forgot what they were called, but theyre constructed to where the center of the tire is a slightly harder compound than the edges so you get longevity from riding highways all the time, and grip in the twisties.
I just got a new set of metzler sportec M1s put on my bike for $326 installed and love them. The bike had RS2s' on it when I got it and they are definatly not something you want for the street. If you're picking up tires for street gow with sportec or Pirelli Diablo Corsa like Blade-runner said.
Metzeler M1s are the best mix of grip and longevity ive ever ridden on. you can get them off of discountmotorcycletire.com for $225 shipped plus around $50 to have them installed at your local dealership