Switched to PR3 tires right at 6K miles ago. Really confident on tight mountain roads here in Colorado. Scrape pegs without a hint of slippage.
Need to change the rear tire. It has flattened in the center. Still some tread, could ride it farther, but it feels "funny" riding on the curves with the flat center area.
Not a bad reflection on the tire, however. My wife and I have a combined rider weight of nearly 400 pounds. We just did a 2000 mile trip from Colorado across Kansas and Missouri to Arkansas in 95-100? F temperatures in June. Straight, very fast and flat through most of Kansas and Missouri. Would guess road surface temperatures to be 110-120?F or so. That should put a flat spot on any tire.
We also just did a 1500 mile trip together last week in Colorado. Although much of that was twisty mountain roads, we also rode a good strectch of I-70 in 90? F temps and some 95-100? strectches in and around Vernal, Utah on flat rough back roads.
The front tire is still in great shape. The sides of the rear tire still look great, too. My guess is that if I did only solo twisty riding, the rear tire would have lasted at least to 9K or more.
I do not ride aggressively in the rain, but I did buy the tires to ride in the rain. Have ridden them in the mountains in heavy rain and they never faltered. On dry roads I tend to multiply speed recommendations in curves by 1.5 to 1.75, but follow them explicitly on wet roads. That said, going 40 MPH on a 40 MPH curve in heavy rain is completely comfortable on the PR3 tires. I often come out of those curves faster but my entry speed matches the recommended speed.
Part of my confidence with these tires may come from their hype on these forums. Nonetheless, I do tend to ride somewhat assertively in the mountains and tar snakes and gravel/sand are my only enemies. On clean asphalt or concrete these are the best tires I have ever ridden.