I've got about 2500 miles on my PR5's and they still look brand new. All other tires I've had on this bike (OEM's, PR3's) really started showing wear around the 3K mile mark. I do a lot of highway and there's no flat spot yet.
I can't say how much better in the rain they are than my old PR3's. I never lost traction in those that I recall but my bike is very planted and stable even in heavy downpours. I will say they are much harder to break loose with DTC off than my PR3's. I've also noticed that even though I take my money sweepers faster than on the PR3's, I still have a little chicken stripe left on my weak side (right) and the strong side bitter edge isn't nearly as scrubbed as the old model. I'm no botanist, but, I think that means they have better traction than the PR3's.