I'm on my second set of Michelin Pilot Powers, second set, because I liked them enough to cough up the money for em. I put about 12000 miles (most were highway, and yes 12 thousand) miles on my first set, and also 90-100 laps at JenningsGP in Florida. They were still great for the first three days after the TrackDay, and then they started to powder up, and break loose. My Second set has about 2000 miles on them, 50% highway, 50% aggressive/high lean angle riding, and have the same contour as the day I bought them.
The Michelins will cup a bit on the front tire after 6k miles , but thats due to the rake angle of the forks. Unfortunately, you'll never be able to escape lunched front tires after high mileage, unless you consistently lean the bike to 1/4-1/3" from the shoulder of the tire.
Also rider style greatly increases/descrease life of your tires, but I believe the dual compound makes a massive difference when it comes being a sportbike/cornering tire, or a highway squared off cruiser tire.
*puts away soapbox*
-EDIT-
Forgot to mention have gone from the 180/55-17 to the 190/50-17; for the sole purpose of greater tread contact in the corners. I've actually been able to use the last 1/4" of front tire tread on either shoulder!!
