I was really happy with my Pilot Roads as well, but had to change them in Califonia on this last trip. Centre of the rear was through ALL the tread at just over 11,000 km (7000 miles). Damn Oregon highway at 95 deg! I changed the front as well, even though it had 35% wear left, as I had hit a pothole so hard, it made me nervous, and the shop only had Bridgestone rears in stock in my size.
I ended up with a BT20 rear, and the new BT21 front. I will let you know how they work out. I would like to try the new Pilot 2's, maybe next set.